Fluorinated cycloolefin polymers, processes for preparation of fluorinated cycloofefin monomers and polymers thereof, and use of the same

ABSTRACT

The present invention is to provide a fluorine-containing polymer having excellent light transmission in the vacuum ultraviolet region of not more than 193 nm, a monomer favorably used for preparing the fluorine-containing polymer, a process for preparing the fluorine-containing polymer, and uses of the fluorine-containing polymer. The fluorine-containing polymer has at least a repeated unit structure represented by the following formula (1) and has an absorption coefficient of not more than 3.0 μm −1  at 157 nm of ultraviolet rays. 
                 
 
wherein R 1  to R 12  are each fluorine, a fluorine-containing alkyl group of 1 to 20 carbon atoms, or the like; X 1  is —CR a R b —, —NR a — or —PR a — (R a  and R b  are each fluorine, a fluorine-containing alkyl group of 1 to 20 carbon atoms, hydrogen, —O—, —S—, an alkyl group of 1 to 20 carbon atoms, or the like); at least one of R 1  to R 12  and X 1  is fluorine or a fluorine-containing group; and n is 0 or an integer of 1 to 3.

This application is the national phase under 35 U.S.C. §371 of PCTInternational Application No. PCT/JP02/04140 which has an Internationalfiling date of Apr. 25, 2002, which designated the United States ofAmerica.

FIELD OF THE INVENTION

The present invention relates to a fluorine-containing cycloolefinpolymer, a cycloolefin monomer thereof, a process for preparing thepolymer and uses of the polymer. More particularly, the inventionrelates to a fluorine-containing cycloolefin polymer which has excellentheat resistance, light resistance and light transmission and isfavorably used as a material for a semiconductor fine process usingvacuum ultraviolet rays, a cycloolefin monomer used as a monomer forpreparing the polymer, a process for preparing the polymer, and uses ofthe fluorine-containing cycloolefin polymer, such as an optical part, athin film, a coating material, a pellicle, a photoresist composition,and a process for forming a pattern by lithography using the photoresistcomposition.

BACKGROUND OF THE INVENTION

In recent years, high integration of semiconductor integrated circuitshas been developed, and large-scale integrated circuits (LSI) or verylarge scale integrated circuits (VLSI) have been put into practical use.With such use, the minimum pattern of the integrated circuit tends to bein the sub-micron region and the lithographic technique tends to becomefiner. For forming a fine pattern, it is essential to use lithographictechnique comprising coating a substrate having a thin film formedthereon with a resist, placing as a dust-proofing film a pellicle overthe resist-coated substrate to prevent adhesion of a foreign substancesuch as dust, conducting light exposure to form a latent image ofdesired pattern, developing the latent image to form a resist pattern,conducting dry etching using the resist pattern as a mask and thenremoving the resist to obtain a desired pattern.

In the lithographic technique, ultraviolet rays of g-line (wavelength:436 nm) or i-line (wavelength: 365 nm) are used as exposure light, andwith fining of patterns, far-ultraviolet rays, vacuum ultraviolet rays,electron beam (EB), X-rays, etc., which have shorter wavelengths, havebeen used as exposure lights. Especially recently, laser beams (KrFexcimer laser beam of a wavelength of 248 nm, ArF excimer laser beam ofa wavelength of 193 nm, F2 laser beam of a wavelength of 157 nm) arepaid attention as exposure lights, and are expected to be useful for theformation of fine patterns.

There is no polymer that transmits a light of such ultraviolet region ofshorter wavelength, particularly the vacuum ultraviolet (VUV) regionsuch as a region of F2 laser beam of 157 nm, and it is difficult toselect a material.

By the way, Bloomstein, et al. have reported that MgF₂ and CaF₂ arepromising optical materials as inorganic optical materials in the fieldusing lights of vacuum ultraviolet region (J. Vac. Sci. Technol. B15,2112, 1997). In this report, it is also reported that, as an organicpolymer material, Teflon (registered trademark) is better than PMMA, PVCand PAA in the transmittance and it exhibits a transmittance of about83% in case of a film of 0.1 μm thickness. It has been further reportedthat with regard to siloxane polymers, methylsiloxane exhibits atransmittance of about 70% in case of a film of 0.1 μm thickness, thoughthe transmittance is not so high.

Examples of the resist materials include a copolymer of a bicyclostructure comprising norbornene having bistrifluoromethyl carbinol as afunctional group and sulfone (ACS Symp. Ser. 706, 208, 1998), acopolymer of a fluorine-containing ethylenically unsaturated compoundmonomer such as tetrafluoroethylene and a polycyclic ethylenicallyunsaturated compound monomer such as norbornene (WO 00/17712), afluorinated polymer obtained from a compound having an ethylenicallydouble bond in which a functional group of bistrifluoroalkyl carbinol—C(Rf)(Rf′)OH (Rf and Rf′ are the same or different fluoroalkyl groups)is introduced, and a copolymer of this fluorinated polymer and TFE (WO00/67072).

Although the OH group tends to improve adhesion to the siliconsubstrate, the OH group present near the fluorine atom is increased inthe acidity and thereby reacts with a carboxylic acid residue formed bythe acid decomposition to cause gelation.

The dust-proofing film such as a pellicle used for the lithographycomprises a pellicle frame made of aluminum or the like and atransparent membrane made of a resin such as nitrocellulose spread onone side surface of the frame, and can be fitted on a mask by, forexample, applying an adhesive on the other side surface of the frame.According to the pellicle, introduction of a foreign substance onto thecircuit pattern surface from the outside can be prevented, and even if aforeign substance adheres to the pellicle membrane, an image of theforeign substance is out of the focal point in the exposure of the lightand is not transferred, so that a trouble hardly takes place.

As described above, use of lights having shorter wavelengths has beenpromoted with the fining down of the minimum pattern of the integratedcircuit, and with this promotion, development of materials of thin filmswithstanding energy of the exposure light of shorter wavelength has beenmade. For example, when KrF excimer laser is used as the exposure lightsource, a fluorine-containing polymer having a relatively smallabsorption in the far-ultraviolet region, such as a commerciallyavailable fluorine-containing resin CYTOP (trade name, available fromAsahi Glass Co., Ltd.) or a commercially available fluorine-containingresin Teflon (registered trademark) AF (trade name, available from U.S.DuPont Co.), is used for a pellicle membrane (Japanese Patent Laid-OpenPublication No. 39963/1991, Japanese Patent Laid-Open Publication No.104155/1992, etc.).

In order to solve a problem of light transmission caused by lightscattering properties due to the crystallizability offluorine-containing polymers synthesized from fluorine-containingethylenically unsaturated compounds such as tetrafluoroethylene andvinylidene fluoride, perfluoro aliphatic cyclic polymers obtained byradical cyclization polymerization of perfluoro bifunctional unsaturatedcompound monomers or radical polymerization of perfluorocyclic monomershave been proposed (Japanese Patent Laid-Open Publications No.238111/1988, No. 131214/1989, No. 131215/1989 and No. 67262/1991), andthese polymers exhibit sufficient transmission to ultraviolet rays of193 nm. Further, it has been reported that a thin film of a copolymer ofethylene tetrafluoride and propylene hexafluoride or a polymer havingsiloxane bond (WO 98/36324) is used as a pellicle membrane whenultraviolet rays having wavelength of 140 to 200 nm are used as exposurelight.

The transmittance of the perfluoro aliphatic cyclic polymers to thevacuum ultraviolet rays of 157 nm is relatively good, but because ofsynthesis by cyclization polymerization, the amount of fluorinecontained in the monomer must be increased, and this causes developmentof water repellency. As a result, adhesion to the substrate isdeteriorated. With regard to polymers which are obtained by ring-openingmetathesis polymerization and has double bond and in which a part offluorine atoms in the perfluoro aliphatic cyclic polymers are replacedwith hydrogen atoms or organic groups, the light transmittance to thevacuum ultraviolet rays of 157 nm is lowered by light absorption of thedouble bond, and the absorption coefficient becomes extremely high.Further, because of the presence of the light absorption band at 157 nm,weathering resistance such as resistance to photodecomposition(photodeterioration) under the circumstances becomes worse, so that suchpolymers cannot be used. Therefore, further development of polymersexcellent in both the weathering resistance and the adhesion and havingextremely low light absorption coefficient in the vacuum ultravioletregion of 157 nm has been desired.

In order to solve the above problems, the present inventors haveearnestly studied fluoropolymers, which are excellent in lighttransmission, optical properties, electrical properties, heatresistance, adhesion to substrate and light resistance and can be usedas base polymers of optical coating materials or resist materials usedfor optical materials, thin films, lenses and the like. As a result, thepresent inventors have found that a novel fluorine-containing polymersatisfies various properties required for the optical coating materialsor resist materials used for optical materials, thin films, lenses andthe like. Based on the finding, the present invention has beenaccomplished.

That is to say, it is an object of the invention to provide a novelfluorine-containing polymer which can be used for optical coatingmaterials or resist materials used for optical materials, thin films,lenses and the like and satisfies light transmission in the vacuumultraviolet region of not more than 193 nm, particularly lighttransmission in the vacuum ultraviolet region of 157 nm, opticalproperties, electrical properties, heat resistance, adhesion tosubstrate and light resistance. It is another object of the invention toprovide a monomer favorably used for preparing the polymer. It is afurther object of the invention to provide a process for preparing thepolymer. It is a still further object of the invention to pvovide usesof the polymer.

DISCLOSURE OF THE INVENTION

The fluorine-containing cycloolefin polymer according to the inventionis characterized by having a repeated unit structure represented by thefollowing formula (1) and having an absorption coefficient of not morethan 3.0 μm⁻¹ to ultraviolet rays of 157 nm;

wherein at least one of R¹ to R¹² and X¹ is the following fluorine orfluorine-containing group,

-   -   R¹ to R¹² are each fluorine or a fluorine-containing group        selected from a fluorine-containing alkyl group of 1 to 20        carbon atoms, a fluorine-containing aryl group of 1 to 20 carbon        atoms, a fluorine-containing and silicon-containing alkyl group        of 1 to 20 carbon atoms, a fluorine-containing alkoxy group of 1        to 20 carbon atoms, a fluorine-containing and ether        group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing alkoxycarbonyl group of 2 to 20 carbon        atoms, a fluorine-containing alkylcarbonyl group of 2 to 20        carbon atoms, a fluorine-containing and ester group-containing        alkyl group of 3 to 20 carbon atoms, a fluorine-containing and        carboxyl group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing and cyano group-containing alkyl group of 2        to 20 carbon atoms, a fluorine-containing and        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        fluorine-containing and bromine-containing alkyl group of 1 to        20 carbon atoms, and a fluorine-containing and iodine-containing        alkyl group of 1 to 20 carbon atoms,    -   X¹ is a fluorine-containing group selected from —CR^(a)R^(b)—,        —NR^(a)— and —PR^(a)— (with the proviso that at least one of        R^(a) and R^(b) in —CR^(a)R^(b)— and R^(a) in —NR^(a)— and        —PR^(a)— are each selected from fluorine, a fluorine-containing        alkyl group of 1 to 20 carbon atoms, a fluorine-containing and        silicon-containing alkyl group of 1 to 20 carbon atoms, a        fluorine-containing alkoxy group of 1 to 20 carbon atoms, a        fluorine-containing and ether group-containing alkyl group of 2        to 20 carbon atoms, a fluorine-containing alkoxycarbonyl group        of 2 to 20 carbon atoms, a fluorine-containing alkylcarbonyl        group of 2 to 20 carbon atoms, a fluorine-containing and ester        group-containing alkyl group of 3 to 20 carbon atoms, a        fluorine-containing and carboxyl group-containing alkyl group of        2 to 20 carbon atoms, a fluorine-containing and cyano        group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing and chlorine-containing alkyl group of 1 to        20 carbon atoms, a fluorine-containing and bromine-containing        alkyl group of 1 to 20 carbon atoms, and a fluorine-containing        and iodine-containing alkyl group of 1 to 20 carbon atoms),    -   R¹ to R¹² other than R¹ to R¹² which are each fluorine or a        fluorine-containing group in the formula (1) are each hydrogen        or a group selected from an alkyl group of 1 to 20 carbon atoms,        a silicon-containing alkyl group of 1 to 20 carbon atoms, an        alkoxy group of 1 to 20 carbon atoms, an alkoxycarbonyl group of        2 to 20 carbon atoms, a carbonyl group, an alkylcarbonyl group        of 2 to 20 carbon atoms, a cyano group, a cyano group-containing        alkyl group of 2 to 20 carbon atoms, an ester group-containing        alkyl group of 3 to 20 carbon atoms, an ether group-containing        alkyl group of 2 to 20 carbon atoms, a hydroxycarbonyl group, a        carboxyl group-containing alkyl group of 2 to 20 carbon atoms, a        hydroxyl group, a hydroxyl group-containing alkyl group of 1 to        20 carbon atoms, chlorine, bromine, iodine, a        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        bromine-containing alkyl group of 1 to 20 carbon atoms and an        iodine-containing alkyl group of 1 to 20 carbon atoms,    -   when X¹ is a group other than a fluorine-containing group, R^(a)        and R^(b) are each hydrogen or a group selected from an alkyl        group of 1 to 20 carbon atoms, a silicon-containing alkyl group        of 1 to 20 carbon atoms, an alkoxy group of 1 to 20 carbon        atoms, an alkoxycarbonyl group of 2 to 20 carbon atoms, a        carbonyl group, an alkylcarbonyl group of 2 to 20 carbon atoms,        a cyano group, a cyano group-containing alkyl group of 2 to 20        carbon atoms, an ester group-containing alkyl group of 3 to 20        carbon atoms, an ether group-containing alkyl group of 2 to 20        carbon atoms, a hydroxycarbonyl group, a carboxyl        group-containing alkyl group of 2 to 20 carbon atoms, a hydroxyl        group, a hydroxyl group-containing alkyl group of 1 to 20 carbon        atoms, chlorine, bromine, iodine, a chlorine-containing alkyl        group of 1 to 20 carbon atoms, a bromine-containing alkyl group        of 1 to 20 carbon atoms and an iodine-containing alkyl group of        1 to 20 carbon atoms, and X¹ may be selected from —O— and —S—,    -   at least two of R¹, R², R¹¹ and R¹² may be bonded to each other        to form a cyclic structure, and    -   n is 0 or an integer of 1 to 3.

The cycloolefin monomer of the fluorine-containing cycloolefin polymeraccording to the invention is represented by the following formula (2)or (3):

wherein at least one of R¹ to R¹ and X¹ in the formula (2) and at leastone of R¹ to R¹⁰ and X¹ in the formula (3) are each fluorine or afluorine-containing group,

-   -   R¹ to R¹² in the formula (2) and R¹ to R¹⁰ in the formula (3)        are each fluorine or a fluorine-containing group selected from a        fluorine-containing alkyl group of 1 to 20 carbon atoms, a        fluorine-containing aryl group of 1 to 20 carbon atoms, a        fluorine-containing and silicon-containing alkyl group of 1 to        20 carbon atoms, a fluorine-containing alkoxy group of 1 to 20        carbon atoms, a fluorine-containing and ether group-containing        alkyl group of 2 to 20 carbon atoms, a fluorine-containing        alkoxycarbonyl group of 2 to 20 carbon atoms, a        fluorine-containing alkylcarbonyl group of 2 to 20 carbon atoms,        a fluorine-containing and ester group-containing alkyl group of        3 to 20 carbon atoms, a fluorine-containing and carboxyl        group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing and cyano group-containing alkyl group of 2        to 20 carbon atoms, a fluorine-containing and        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        fluorine-containing and bromine-containing alkyl group of 1 to        20 carbon atoms, and a fluorine-containing and iodine-containing        alkyl group of 1 to 20 carbon atoms,    -   X¹ in the formulas (2) and (3) is a fluorine-containing group        selected from —CR^(a)R^(b)—, —NR^(a)— and —PR^(a)— (with the        proviso that at least one of R^(a) and R^(b) in —CR^(a)R^(b)—        and R^(a) in —NR^(a)— and —PR^(a)— are each selected from        fluorine, a fluorine-containing alkyl group of 1 to 20 carbon        atoms, a fluorine-containing and silicon-containing alkyl group        of 1 to 20 carbon atoms, a fluorine-containing alkoxy group of 1        to 20 carbon atoms, a fluorine-containing and ether        group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing alkoxycarbonyl group of 2 to 20 carbon        atoms, a fluorine-containing alkylcarbonyl group of 2 to 20        carbon atoms, a fluorine-containing and ester group-containing        alkyl group of 3 to 20 carbon atoms, a fluorine-containing and        carboxyl group-containing alkyl group of 2 to 20 carbon atoms, a        fluorine-containing and cyano group-containing alkyl group of 2        to 20 carbon atoms, a fluorine-containing and        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        fluorine-containing and bromine-containing alkyl group of 1 to        20 carbon atoms, and a fluorine-containing and iodine-containing        alkyl group of 1 to 20 carbon atoms),    -   R¹ to R¹² other than R¹ to R¹² which are each fluorine or a        fluorine-containing group in the formula (2) and R¹ to R¹⁰ other        than R¹ to R¹⁰ which are each fluorine or a fluorine-containing        group in the formula (3) are each hydrogen or a group selected        from an alkyl group of 1 to 20 carbon atoms, a        silicon-containing alkyl group of 1 to 20 carbon atoms, an        alkoxy group of 1 to 20 carbon atoms, an alkoxycarbonyl group of        2 to 20 carbon atoms, a carbonyl group, an alkylcarbonyl group        of 2 to 20 carbon atoms, a cyano group, a cyano group-containing        alkyl group of 2 to 20 carbon atoms, an ester group-containing        alkyl group of 3 to 20 carbon atoms, an ether group-containing        alkyl group of 2 to 20 carbon atoms, a hydroxycarbonyl group, a        carboxyl group-containing alkyl group of 2 to 20 carbon atoms, a        hydroxyl group, a hydroxyl group-containing alkyl group of 1 to        20 carbon atoms, chlorine, bromine, iodine, a        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        bromine-containing alkyl group of 1 to 20 carbon atoms and an        iodine-containing alkyl group of 1 to 20 carbon atoms,    -   when X¹ is a group other than a fluorine-containing group in the        formulas (2) and (3), R^(a) and R^(b) are each hydrogen or a        group selected from an alkyl group of 1 to 20 carbon atoms, a        silicon-containing alkyl group of 1 to 20 carbon atoms, an        alkoxy group of 1 to 20 carbon atoms, an alkoxycarbonyl group of        2 to 20 carbon atoms, a carbonyl group, an alkylcarbonyl group        of 2 to 20 carbon atoms, a cyano group, a cyano group-containing        alkyl group of 2 to 20 carbon atoms, an ester group-containing        alkyl group of 3 to 20 carbon atoms, an ether group-containing        alkyl group of 2 to 20 carbon atoms, a hydroxycarbonyl group, a        carboxyl group-containing alkyl group of 2 to 20 carbon atoms, a        hydroxyl group, a hydroxyl group-containing alkyl group of 1 to        20 carbon atoms, chlorine, bromine, iodine, a        chlorine-containing alkyl group of 1 to 20 carbon atoms, a        bromine-containing alkyl group of 1 to 20 carbon atoms and an        iodine-containing alkyl group of 1 to 20 carbon atoms, and X¹        may be selected from —O— and —S—,    -   R¹, R², R¹¹ and R¹² in the formula (2) may be bonded to each        other to form a cyclic structure, and R¹ and R² in the        formula (3) may be bonded to each other to form a cyclic        structure, and    -   n is 0 or an integer of 1 to 3.

The process for preparing a fluorine-containing cycloolefin polymeraccording to the invention comprises subjecting at least one cycloolefinmonomer represented by the formula (2) or (3) to ring-opening metathesispolymerization and then subjecting the obtained ring-opening metathesispolymer to at least one of hydrogenation, hydrogen fluoride addition andfluorine addition.

In the fluorine-containing cycloolefin polymer according to theinvention, the repeated unit structure represented by the formula (1) isa repeated unit structure having a feature that the difference in theHOMO molecular orbital energy between a molecular model in which methylgroup is bonded to each end of the unit structure and a molecular modelwhich has the same carbon structure as the above molecular model but inwhich fluorine is replaced with hydrogen is in the range of 0.2 eV to1.5 eV.

In the cycloolefin monomer, the total sum of the number of all fluorineatoms contained in R¹ to R¹² in the formula (2) and the total sum of thenumber of all fluorine atoms contained in R¹ to R¹⁰ in the formula (3)are each not less than 3.

The fluorine-containing cycloolefin polymer according to the inventionis preferably a polymer obtained using, as starting monomers, two ormore cycloolefin monomers represented by the formula (2) or (3) anddifferent from each other in at least one of R¹ to R¹², R¹ to R¹⁰, X¹and n. The fluorine-containing cycloolefin polymer is also preferably apolymer obtained using, as starting monomers, at least one cycloolefinmonomer of the formula (2) or (3) wherein X¹ is —CR^(a)R^(b)— and atleast one cycloolefin monomer of the formula (2) or (3) wherein X¹ is—O—. The fluorine-containing cycloolefin polymer is also a polymerobtained using, as starting monomers, the cycloolefin monomerrepresented by the formula (2) or (3) and a fluorine-containingmonocycloolefin.

The fluorine-containing cycloolefin polymer according to the inventionhas a weight-average molecular weight (Mw), as measured by gelpermeation chromatography (GPC), of 500 to 1,000,000 in terms ofpolystyrene.

Each of the optical part, the thin film and the coating materialaccording to the invention comprises the fluorine-containing cycloolefinpolymer. The pellicle according to the invention uses the thin filmcomprising the fluorine-containing cycloolefin polymer. The photoresistcomposition according to the invention contains the fluorine-containingcycloolefin polymer.

The process for forming a pattern by lithography according to theinvention uses any one of the optical part, the thin film, the coatingmaterial, the pellicle and the photoresist composition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows VUV spectra of fluorine-containing cycloolefin polymers ofExample 1 and Example 2.

FIG. 2 shows VUV spectra of fluorine-containing cycloolefin polymers ofExample 8 and Example 9.

FIG. 3 shows a ¹³C-NMR spectrum of a fluorine-containing cycloolefinpolymer of Example 8.

FIG. 4 shows a ¹³C-NMR spectrum of a fluorine-containing cycloolefinpolymer of Example 9.

FIG. 5 shows a VUV spectrum of a pellicle membrane formed from afluorine-containing cycloolefin polymer of Example 14.

FIG. 6 is a simple structural view of a pellicle. In FIG. 6, numeral 1designates a pellicle membrane, numeral 2 designates a membraneadhesive, numeral 3 designates a frame, numeral 4 designates a maskadhesive, numeral 5 designates a liner, and numeral 6 designates aninside wall tacky agent.

PREFERRED EMBODIMENTS OF THE INVENTION

The fluorine-containing cycloolefin polymer according to the invention,the cycloolefin monomer of the polymer, the process for preparing thepolymer and uses of the polymer are described in detail hereinafter.

Fluorine-Containing Cycloolefin Polymer

The fluorine-containing cycloolefin polymer according to the inventionhas at least a unit structure represented by the following formula (1)in the repeated units of the polymer.

In the formula (1), at least one of R¹ to R¹² and X¹ is fluorine or afluorine-containing group.

When at least one of R¹ to R¹² is fluorine or a fluorine-containinggroup, R¹ to R¹² are each, for example, fluorine or afluorine-containing group selected from:

-   -   a fluorine-containing alkyl group of 1 to 20 carbon atoms, such        as fluoromethyl, difluoromethyl, trifluoromethyl,        trifluoroethyl, pentafluoroethyl, hexafluoroisopropyl,        heptafluoroisopropyl, heptafluoropropyl,        hexafluoro-2-methylisopropyl, nonafluorobutyl or        perfluorocyclopentyl;    -   a fluorine-containing aryl group of 1 to 20 carbon atoms, such        as pentafluorophenyl or heptafluoronaphthyl;    -   a fluorine-containing and silicon-containing alkyl group of 1 to        20 carbon atoms, such as trifluoropropyldimethylsilyl,        tris(trifluoromethyl)silyl or        perfluorooctyldi(trifluoromethyl)silyl;    -   a fluorine-containing alkoxy group of 1 to 20 carbon atoms, such        as trifluoromethoxy, trifluoroethoxy, pentafluoropropoxy,        pentafluorobutoxy, hexafluoro-2-methylisopropoxy,        heptafluorobutoxy, perfluorocyclopentoxy,        tetrafluoropyran-2-yloxy or perfluorofuran-2-yloxy;    -   a fluorine-containing and ether group-containing alkyl group of        2 to 20 carbon atoms, such as trifluoromethoxymethyl,        trifluoroethoxymethyl, pentafluoropropoxymethyl,        pentafluorobutoxymethyl, hexafluoro-2-methylisopropoxymethyl,        heptafluorobutoxymethyl, 2,2-di(trifluoromethyl)dioxolanmethyl,        tetrafluoropyran-2-yloxymethyl or perfluorofuran-2-yloxymethyl;    -   a fluorine-containing alkoxycarbonyl group of 2 to 20 carbon        atoms, such as trifluoromethoxycarbonyl,        trifluoroethoxycarbonyl, pentafluoropropoxycarbonyl,        pentafluorobutoxycarbonyl,        hexafluoro-2-methylisopropoxycarbonyl,        heptafluorobutoxycarbonyl, perfluorocyclopentoxycarbonyl,        tetrafluoropyran-2-yloxycarbonyl or        perfluorofuran-2-yloxycarbonyl;    -   a fluorine-containing alkylcarbonyl group of 2 to 20 carbon        atoms, such as trifluoromethylcarbonyl, trifluoroethylcarbonyl,        pentafluoropropylcarbonyl, pentafluorobutylcarbonyl,        hexafluoro-2-methylisopropylcarbonyl, heptafluorobutylcarbonyl,        perfluorocyclopentylcarbonyl, tetrafluoropyran-2-ylcarbonyl or        perfluorofuran-2-ylcarbonyl;    -   a fluorine-containing and ester group-containing alkyl group of        3 to 20 carbon atoms, such as carbotrifluoromethoxymethyl,        carbotrifluoroethoxymethyl, carbopentafluoropropoxymethyl,        carbopentafluorobutoxymethyl,        carbo(hexafluoro-2-methylisopropoxy)methyl,        carboheptafluorobutoxymethyl, carboperfluorocyclopentoxymethyl,        carbotetrafluoropyran-2-yloxymethyl or        carboperfluorofuran-2-yloxymethyl;    -   a fluorine-containing and carboxyl group-containing alkyl group        of 2 to 20 carbon atoms, such as carboxytrifluoromethyl,        carboxytetrafluoroethyl, carboxyhexafluoroisopropyl,        carboxyhexafluoro-2-methylisopropyl or        carboxyperfluorocyclopentyl;    -   a fluorine-containing and cyano group-containing alkyl group of        2 to 20 carbon atoms, such as 1-cyanotetrafluoroethyl or        1-cyanohexafluoropropyl; and    -   a fluorine-containing and chlorine-containing alkyl group of 1        to 20 carbon atoms, a fluorine-containing and bromine-containing        alkyl group of 1 to 20 carbon atoms and a fluorine-containing        and iodine-containing alkyl group of 1 to 20 carbon atoms, such        as bromotrifluoroethyl, bromotetrafluoroethyl,        2-bromotetrafluoroisopropyl and        hexafluoro-2-bromomethylisopropyl.

When at least one X¹ is a fluorine-containing group, X¹ is selected fromfluorine-containing groups, such as —CR^(a)R^(b)—, —NR^(a)— and—PR^(a)—.

At least one of R^(a) and R^(b) in —CR^(a)R^(b)— and R^(a) in —NR^(a)—and —PR^(a)— are each selected from fluorine, a fluorine-containingalkyl group of 1 to 20 carbon atoms, a fluorine-containing andsilicon-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing alkoxy group of 1 to 20 carbon atoms, afluorine-containing and ether group-containing alkyl group of 1 to 20carbon atoms, a fluorine-containing alkoxycarbonyl group of 1 to 20carbon atoms, a fluorine-containing alkylcarbonyl group of 1 to 20carbon atoms, a fluorine-containing and ester group-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing and carboxylgroup-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing and cyano group-containing alkyl group of 1 to 20carbon atoms, a fluorine-containing and chlorine-containing alkyl groupof 1 to 20 carbon atoms, a fluorine-containing and bromine-containingalkyl group of 1 to 20 carbon atoms, and a fluorine-containing andiodine-containing alkyl group of 1 to 20 carbon atoms. Examples of thesegroups include the same fluorine-containing groups as previouslydescribed with respect to R¹ to R¹².

When two or more of R¹ to R¹² in the formula (1) are each fluorine or afluorine-containing group, they may be the same or different, and whentwo or more of X¹ in the formula (1) are each a fluorine-containinggroup, they may be the same or different.

In the formula (1), R¹ to R¹² other than R¹ to R¹² which are eachfluorine or a fluorine-containing group are each, for example, hydrogen,chlorine, bromine, iodine or a group selected from:

-   -   an alkyl group of 1 to 20 carbon atoms, such as methyl, ethyl,        propyl, isopropyl, n-butyl, tert-butyl, cyclohexyl or menthyl;    -   a silicon-containing alkyl group of 1 to 20 carbon atoms, such        as trimethylsilyl, dimethylethylsilyl or        dimethylcyclopentylsilyl;    -   an alkoxy group of 1 to 20 carbon atoms, such as methoxy,        ethoxy, isopropoxy, tert-butoxy or menthoxy;    -   an alkoxycarbonyl group of 2 to 20 carbon atoms, such as        methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl,        isopropoxycarbonyl, n-butoxycarbonyl, tert-butoxycarbonyl,        cyclohexyloxycarbonyl, tetrahydropyran-2-yloxycarbonyl,        tetrahydrofuran-2-yloxycarbonyl, 1-ethoxyethoxycarbonyl or        1-butoxyethoxycarbonyl;    -   a carbonyl group;    -   an alkylcarbonyl group of 2 to 20 carbon atoms, such as        methylcarbonyl, ethylcarbonyl, n-propylcarbonyl,        isopropylcarbonyl, n-butylcarbonyl, tert-butylcarbonyl,        cyclohexylcarbonyl, tetrahydropyran-2-ylcarbonyl or        tetrahydrofuran-2-ylcarbonyl;    -   a cyano group;    -   a cyano group-containing alkyl group of 2 to 20 carbon atoms,        such as cyanomethyl, cyanoethyl, cyanopropyl, cyanobutyl or        cyanohexyl;    -   an ester group-containing alkyl group of 3 to 20 carbon atoms,        such as carbomethoxymethyl, carboethoxymethyl,        carbopropoxymethyl, carbobutoxymethyl,        carbo(2-methylisopropoxy)methyl, carbobutoxyethyl,        carbocyclopentoxymethyl, carbo(tetrahydropyran-2-yloxy)methyl or        carbo(tetrahydrofuran-2-yloxy)methyl;    -   an ether group-containing alkyl group of 2 to 20 carbon atoms,        such as methoxymethyl, ethoxymethyl, propoxymethyl,        butoxymethyl, 2-methylisopropoxymethyl, butoxymethyl,        2,2-dimethyldioxolanmethyl, tetrahydropyran-2-yloxymethyl or        tetrahydrofuran-2-yloxymethyl;    -   a hydroxycarbonyl group;    -   a carboxyl group-containing alkyl group of 2 to 20 carbon atoms,        such as carboxymethyl, carboxyethyl or carboxypropyl;    -   a hydroxyl group;    -   a hydroxyl group-containing alkyl group of 1 to 20 carbon atoms,        such as hydroxymethyl, hydroxyethyl, hydroxypropyl,        hydroxybutyl, hydroxyhexyl, menthol or saccharide (e.g.,        glucose); and    -   a chlorine-containing alkyl group of 1 to 20 carbon atoms, a        bromine-containing alkyl group of 1 to 20 carbon atoms and an        iodine-containing alkyl group of 1 to 20 carbon atoms, such as        chloromethyl, bromomethyl, iodomethyl, dichloromethyl,        dibromomethyl, diiodomethyl, trichloromethyl, tribromomethyl and        triiodomethyl.

When X¹ is a group other than a fluorine-containing group, R^(a) andR^(b) are each, for example, hydrogen, chlorine, bromine, iodine or agroup selected from an alkyl group of 1 to 20 carbon atoms, asilicon-containing alkyl group of 1 to 20 carbon atoms, an alkoxy groupof 1 to 20 carbon atoms, an alkoxycarbonyl group of 2 to 20 carbonatoms, a carbonyl group, an alkylcarbonyl group of 2 to 20 carbon atoms,a cyano group, a cyano group-containing alkyl group of 2 to 20 carbonatoms, an ester group-containing alkyl group of 3 to 20 carbon atoms, anether group-containing alkyl group of 2 to 20 carbon atoms, ahydroxycarbonyl group, a carboxyl group-containing alkyl group of 2 to20 carbon atoms, a hydroxyl group, a hydroxyl group-containing alkylgroup of 1 to 20 carbon atoms, a chlorine-containing alkyl group of 1 to20 carbon atoms, a bromine-containing alkyl group of 1 to 20 carbonatoms and an iodine-containing alkyl group of 1 to 20 carbon atoms.Examples of these groups include the same groups containing no fluorineas previously described with respect to R¹ to R¹². X¹ may be —O— or —S—.

When X¹ is a group other than a fluorine-containing group, X¹ ispreferably —O— or —CH₂—.

When there are two or more groups other than fluorine or afluorine-containing group as R¹ to R¹² and X¹, they may be the same ordifferent.

At least two of R¹, R², R¹¹ and R¹² may be bonded to each other to forma cyclic structure.

n is 0 or an integer of 1 to 3, preferably 0 or 1.

The fluorine-containing cycloolefin polymer of the invention may beformed from only a repeated unit structure represented by the formula(1), or may contain a repeated unit structure other than the repeatedunit structure represented by the formula (1).

In the fluorine-containing cycloolefin polymer of the invention, thetotal sum of the number of all fluorine atoms contained in R¹ to R¹² inthe repeated unit structure represented by the formula (1) is preferablynot less than 3.

If the total sum of the number of all fluorine atoms is 1 or 2, theshorter wavelength shift of the ultraviolet absorption wavelength due tothe inductive effect of fluorine is not satisfactory. Therefore, thelight transmission at 157 nm is not improved, and the absorptioncoefficient sometimes becomes higher than 3 μm⁻¹. The total sum of thenumber of all fluorine atoms is preferably in the range of 3 to 30.

The repeated unit structure other than the repeated unit structurerepresented by the formula (1) is, for example, a repeated unitstructure derived from a cycloolefin containing or not containingfluorine, which is used together with the cycloolefin represented by thelater-described formula (2) or (3) in the metathesis polymerization ofat least one cycloolefin represented by the formula (2) or (3).

The fluorine-containing cycloolefin polymer of the invention ispreferably a polymer consisting of only one kind of the unit structurerepresented by the formula (1), or is also preferably a polymerconsisting of two or more kinds of the unit structures which aredifferent in at least one of R¹ to R¹², X¹ and n in the formula (1), oris also preferably a polymer consisting of at least one kind of the unitstructure wherein X¹ in the formula (1) is —CR^(a)R^(b)— and at leastone kind of the unit structure wherein X¹ in the formula (1) is —O—, oris preferably a polymer consisting of the unit structure represented bythe formula (1) and a unit structure derived from a fluorine-containingmonocycloolefin.

When a thin film such as a pellicle membrane is bonded or press bondedto an aluminum frame, the fluorine-containing cycloolefin polymersconsisting of two or more kinds of the unit structures which aredifferent in at least one of R¹ to R¹², X¹ and n in the formula (1) andthe fluorine-containing cycloolefin polymer consisting of at least onekind of the unit structure wherein X¹ in the formula (1) is—CR^(a)R^(b)— and at least one kind of the unit structure wherein X¹ inthe formula (1) is —O— exhibit excellent adhesion to the metal frame.Further, when these polymers are applied onto a silicon wafer asphotoresist and exposed to light, they exhibit excellent adhesionproperties to the wafer. Moreover, the resolution of the photoresist orthe solubility (developing properties) of the photoresist in an alkalinedeveloping solution can be arbitrarily determined by changing theproportions between the above unit structures, and the properties of theresist can be appropriately selected. Especially for improving the bondproperties, adhesion properties, and developing properties, X¹ ispreferably —O—.

The repeated unit structure other than the repeated unit structurerepresented by the formula (1) may be contained in thefluorine-containing cycloolefin polymer in an amount of not more than90% by mol, preferably not more than 30% by mol.

The fluorine-containing cycloolefin polymer of the invention has aweight-average molecular weight (Mw), as measured by gel permeationchromatography (GPC), of 500 to 1,000,000 in terms of polystyrene,preferably 3,000 to 500,000. The molecular weight distribution Mw/Mn ofthe polymer is in the range of preferably 1.0 to 3.0.

If the weight-average molecular weight Mw is less than 500, propertiesof the polymer are not exhibited, and the light resistance sometimesbecomes poor. If the weight-average molecular weight is more than1,000,000, bad influences due to lowering of flowability are sometimesexerted on the film-forming properties or the spin coating properties ofa thin film, a coating material and a photoresist material. Likewise, ifthe molecular weight distribution Mw/Mn is more than 3.0, bad influencesare sometimes exerted on the film-forming properties or the spin coatingproperties of a thin film such as pellicle membrane, a coating materialand a photoresist material.

In the fluorine-containing cycloolefin polymer of the invention, therepeated unit structure represented by the formula (1) is preferably arepeated unit structure having a feature that the difference in the HOMOmolecular orbital energy between a molecular model in which methyl groupis bonded to each end of the unit structure and a molecular model whichhas the same carbon structure as the above molecular model but in whichfluorine is replaced with hydrogen is in the range of 0.2 eV to 1.5 eV.

The term “HOMO” used herein means “Highest Occupied Molecular Orbital”,and the difference in the HOMO energy is, for example, an energydifference calculated by the semiempirical orbital method (PM3 method)between a HOMO energy of a molecular model (chemical formula (1′)) inwhich both ends of a repeated structural unit of the formula (1) whereinR² is CF₃, X¹ is CH₂, the others are each hydrogen, and n is 0 arecapped with methyl groups in a hydrogenated polymer of a ring-openingmetathesis polymer and a HOMO energy of a molecular model (chemicalformula (1″)) wherein fluorine in the molecular model of the chemicalformula (1′) is replaced with hydrogen.

(Molecular model in which both ends of a repeated structural unit of theformula (1) wherein R² is CF₃, X¹ is CH₂, the others are each hydrogen,and n is 0 are capped with methyl groups in a hydrogenated polymer of aring-opening metathesis polymer.)

(Molecular model in which both ends of a repeated structural unit of theformula (1) wherein R² is CF₃, X¹ is CH₂, the others are each hydrogen,and n is 0 are capped with methyl groups, and fluorine is replaced withhydrogen in a hydrogenated polymer of a ring-opening metathesispolymer.)

When the HOMO energy difference is in the range of 0.2 eV to 1.5 eV, theabsorption coefficient of the fluorine-containing polymer at 157 nm ofvacuum ultraviolet rays becomes not more than 3.0 μm⁻¹. The HOMO energydifference between the structural unit molecular models can well expressthe degree of the absorption coefficient.

The absorption coefficient of the fluorine-containing cycloolefinpolymer of the invention at 157 nm of vacuum ultraviolet rays is notmore than 3.0 μm⁻¹. If the absorption coefficient at this wavelengthexceeds 3.0 μm⁻¹, the polymer is deteriorated by the absorption energyof the light to cause lowering of light resistance of the resist or tocause marked light energy loss when used for a pellicle membrane etc.,and thereby troubles may occur in the semiconductor production. Further,because of light energy loss caused by the light energy absorption, alight quantity capable of forming an extremely fine pattern in theproduction of semiconductor or the like cannot be attained, and therebya problem that the polymer cannot apply to the lithographic processingusing vacuum ultraviolet rays may occur.

In the present invention, the absorption coefficient is represented bythe following common logarithmic equation.Absorption coefficient (μm⁻¹)=Log₁₀ [T ₀ /T _(s) ]/t _(s)  (1)

In the equation (1), the unit of the absorption coefficient is expressedin a reciprocal number of the thickness μm of a film or a spin-coatingfilm formed on a CaF₂ substrate, and T_(o) is a transmittance of ablank, that is to say, when the sample is a film, T_(o) is atransmittance in the measuring atmosphere, and when the sample is aspin-coating film formed on a CaF₂ substrate, T_(o) is a transmittanceof the uncoated substrate, namely, a transmittance measured before thecoating. T_(s) is a transmittance of the sample film or the sampleapplied onto the CaF₂ substrate. These transmittances can be measured bya vacuum ultraviolet spectroscope. t_(s) is a thickness of the samplefilm or the sample applied onto the CaF₂ substrate, and is expressed inμm.

The fluorine-containing cycloolefin polymer of the invention hasexcellent light transmission over a wide range of visible region tovacuum ultraviolet region and has a low light refractive index. Therefractive index in the visible region is not more than 1.50.

The light transmittance of the fluorine-containing cycloolefin polymerin the visible region is in the range of 95 to 100%, and the lighttransmittance in the region of ultraviolet rays from KrF excimer laseror ArF excimer laser is high and in the range of 80 to 100%.

The glass transition temperature (Tg) that is an indication of thermalresistance of a polymer depends upon structure or molecular weight ofthe polymer, and it is possible to design a fluorine-containingcycloolefin polymer having Tg of not lower than 100° C. Owing to itsoptical properties and thermal properties, the polymer having high Tgcan be used for optical parts. Further, designing of the cycloolefinpolymer structure makes it possible to impart chemical resistance andwater resistance to the fluorine-containing cycloolefin polymer.

The fluorine-containing cycloolefin polymer having at least a repeatedunit structure represented formula (I) of the invention is prepared by,for example, a process comprising subjecting at least one cycloolefinmonomer represented by the formula (2) or (3) to ring-opening metathesispolymerization and then subjecting the obtained ring-opening metathesispolymer to at least one of hydrogenation, hydrogen fluoride addition andfluorine addition.

Next, the cycloolefin monomer preferably used for the synthesis of thefluorine-containing cycloolefin polymer of the invention is described.

Cycloolefin Monomer

The cycloolefin monomer of the fluorine-containing cyclolefin polymer ofthe invention is represented by the following formula (2) or (3).

In the formula (2), at least one of R¹ to R¹² and X¹ is fluorine or afluorine-containing group, and in the formula (3), at least one of R¹ toR¹⁰ and X¹ is fluorine or a fluorine-containing group.

When at least one of R¹ to R¹² in the formula (2) and at least one of R¹to R¹⁰ in the formula (3) are each fluorine or a fluorine-containinggroup, R¹ to R¹² and R¹ to R¹⁰ are each, for example, fluorine or afluorine-containing group selected from a fluorine-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing aryl group of 1 to20 carbon atoms, a fluorine-containing and silicon-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing alkoxy group of 1to 20 carbon atoms, a fluorine-containing and ether group-containingalkyl group of 2 to 20 carbon atoms, a fluorine-containing alkylcarbonylgroup of 2 to 20 carbon atoms, a fluorine-containing and estergroup-containing alkyl group of 3 to 20 carbon atoms, afluorine-containing and carboxyl group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing and cyano group-containing alkylgroup of 2 to 20 carbon atoms, a fluorine-containing andchlorine-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing and bromine-containing alkyl group of 1 to 20 carbonatoms, and a fluorine-containing and iodine-containing alkyl group of 1to 20 carbon atoms. Examples of these groups include the samefluorine-containing groups as previously described with respect to R¹ toR¹² in the formula (1).

When at least one X¹ in the formulas (2) and (3) is afluorine-containing group, X¹ is selected from fluorine-containinggroups, such as —CR^(a)R^(b)—, —NR^(a)— and —PR^(a)—.

At least one of R^(a) and R^(b) in —CR^(a)R^(b)— and R^(a) in —NR^(a)—and —PR^(a)— are each selected from fluorine, a fluorine-containingalkyl group of 1 to 20 carbon atoms, a fluorine-containing andsilicon-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing alkoxy group, a fluorine-containing and ethergroup-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing alkoxycarbonyl group of 2 to 20 carbon atoms, afluorine-containing alkylcarbonyl group of 2 to 20 carbon atoms, afluorine-containing and ester group-containing alkyl group of 3 to 20carbon atoms, a fluorine-containing and carboxyl group-containing alkylgroup of 2 to 20 carbon atoms, a fluorine-containing and cyanogroup-containing alkyl group of 2 to 20 carbon atoms, afluorine-containing and chlorine-containing alkyl group of 1 to 20carbon atoms, a fluorine-containing and bromine-containing alkyl groupof 1 to 20 carbon atoms, and a fluorine-containing and iodine-containingalkyl group of 1 to 20 carbon atoms. Examples of these groups includethe same fluorine-containing groups as previously described with respectto R¹ to R¹² in the formula (1).

When two or more of R¹ to R¹² in the formula (2) are each fluorine or afluorine-containing group, they may be the same or different, and whentwo or more of X¹ in the formula (2) are each a fluorine-containinggroup, they may be the same or different. When two or more of R¹ to R¹⁰in the formula (3) are each fluorine or a fluorine-containing group,they may be the same or different, and when two or more of X¹ in theformula (3) are each a fluorine-containing group, they may be the sameor different.

R¹ to R¹² other than R¹ to R¹² which are each fluorine or afluorine-containing group in the formula (2) and R¹ to R¹⁰ other than R¹to R¹⁰ which are each fluorine or a fluorine-containing group in theformula (3) are each selected from, for example, hydrogen, an alkylgroup of 1 to 20 carbon atoms, a silicon-containing alkyl group of 1 to20 carbon atoms, an alkoxy group of 1 to 20 carbon atoms, analkoxycarbonyl group of 2 to 20 carbon atoms, a carbonyl group, analkylcarbonyl group of 2 to 20 carbon atoms, a cyano group, a cyanogroup-containing alkyl group of 2 to 20 carbon atoms, an estergroup-containing alkyl group of 3 to 20 carbon atoms, an ethergroup-containing alkyl group of 2 to 20 carbon atoms, a hydroxycarbonylgroup, a carboxyl group-containing alkyl group of 2 to 20 carbon atoms,a hydroxyl group, a hydroxyl group-containing alkyl group of 1 to 20carbon atoms, chlorine, bromine, iodine, a chlorine-containing alkylgroup of 1 to 20 carbon atoms, a bromine-containing alkyl group of 1 to20 carbon atoms and an iodine-containing alkyl group of 1 to 20 carbonatoms. Examples of these groups include the same groups containing nofluorine as previously described with respect to R¹ to R¹² in theformula (1).

When X¹ is a group other than a fluorine-containing group in theformulas (2) and (3), R^(a) and R^(b) are each selected from, forexample, hydrogen, chlorine, bromine, iodine, an alkyl group of 1 to 20carbon atoms, a silicon-containing alkyl group of 1 to 20 carbon atoms,an alkoxy group of 1 to 20 carbon atoms, an alkoxycarbonyl group of 2 to20 carbon atoms, a carbonyl group, an alkylcarbonyl group of 2 to 20carbon atoms, a cyano group, a cyano group-containing alkyl group of 2to 20 carbon atoms, an ester group-containing alkyl group of 3 to 20carbon atoms, an ether group-containing alkyl group of 2 to 20 carbonatoms, a hydroxycarbonyl group, a carboxyl group-containing alkyl groupof 2 to 20 carbon atoms, a hydroxyl group, a hydroxyl group-containingalkyl group of 1 to 20 carbon atoms, a chlorine-containing alkyl groupof 1 to 20 carbon atoms, a bromine-containing alkyl group of 1 to 20carbon atoms and an iodine-containing alkyl group of 1 to 20 carbonatoms. Examples of these groups include the same groups containing nofluorine as previously described with respect to R¹ to R¹² in theformula (1).

X¹ may be selected from —O— and —S—.

n is 0 or an integer of 1 to 3.

When X¹ is a group other than a fluorine-containing group, X¹ ispreferably —O— or —CH₂—.

When there are two or more groups other than fluorine or afluorine-containing group as R¹ to R¹² in the formula (2), they may bethe same or different, and when there are two or more groups other thanfluorine or a fluorine-containing group as X¹ in the formula (2), theymay be the same or different. When there are two or more groups otherthan fluorine or a fluorine-containing group as R¹ to R¹⁰ in the formula(3), they may be the same or different, and when there are two or moregroups other than fluorine or a fluorine-containing group as X¹ in theformula (3), they may be the same or different.

In the formula (2), R¹, R², R¹¹ and R¹² may be bonded to each other toform a cyclic structure, and in the formula (3), R¹ and R² may be bondedto each other to form a cyclic structure.

Examples of the cycloolefin monomers represented by the formula (2)include 5-trifluoromethylbicyclo[2.2.1]hept-2-ene,5-trifluoromethyl-7-oxobicyclo[2.2.1]hept-2-ene,5,6-difluoro-5,6-bistrifluoromethylbicyclo[2.2.1]hept-2-ene,5,6-difluoro-5-trifluoromethyl-6-pentafluorobicyclo[2.2.1]hept-2-ene,5-fluoro-5-pentafluoroethyl-6,6-bistrifluoromethylbicyclo[2.2.1]hept-2-ene,5,6-difluoro-5-trifluoromethyl-6-heptafluoroisopropylbicyclo[2.2.1]hept-2-ene,5,6,6,7,7,8,8,9-octafluorotricyclo[5.2.1.0^(5.9)]deca-2-ene and5,6-bis(nonafluorobutyl)bicyclo[2.2.1]hept-2-ene.

For example, there can be mentioned the following structures.

wherein

-   -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃C₇, C₄C₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R* is H, R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br, and    -   R and R* are independent from each other.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R″ is R′,    -   R* is H or R′, and    -   R, R′, R″ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S.    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R″ is R′,    -   R″′ is R′,    -   R* is H or R′, and    -   R, R′, R″, R″′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is CF₂, CFCF, CHCF₃, C(CF₃)₂, (CF₂)₂, (CF₂)₃, CHC₆F₅,        Si(CF₃)₂, CF₂OCF₂, CFOH, COCF₂, CFCOOCF₂, CFCOOH or CFCN,    -   R′ is R, CH₂, (CH₂)₂, (CH₂)₃, Si(CH₃)₂, CH₂OCH₂, CHOH, COOCH₂,        CHCOOH, CO, CHOCH₃, O or CHOCHOCH₃,    -   R* is H, F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁,        C₆F₅, Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is CF₂, CFCF, CHCF₃, C(CF₃)₂, (CF₂)₂, (CF₂)₃, CHC₆F₅,        Si(CF₃)₂, CF₂OCF₂, CFOH, COCF₂, CFCOOCF₂, CFCOOH, CFCN, CH₂,        (CH₂)₂, (CH₂)₃, Si(CH₃)₂, CH₂OCH₂, CHOH, COOCH₂, CHCOOH, CO,        CHOCH₃ or CHOCHOCH₃,    -   R′ is R,    -   R″ is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁,        C₆F₅, Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br,    -   R″′ is R″,    -   R* is H or R″, and    -   R, R′, R″, R″′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is (CF₂)₂, (CF₂)₃, (CF₂)₄, (CF₂)₅ or (CF₂)₆,    -   R′ is R, CH₂, (CH₂)₂, (CH₂)₃, (CH₂)₄, (CH₂)₅ or (CH₂)₆,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   Y is O, CO, NCF₃, NCH₃ or NC₆F₅,    -   R is CF₂, CFCF, CHCF₃, C(CF₃)₂, (CF₂)₂, (CF₂)₃, CHC₆F₅,        Si(CF₃)₂, CF₂OCF₂, CFOH, COCF₂, CFCOOCF₂, CFCOOH or CFCN,    -   R′ is R, CH₂, (CH₂)₂, (CH₂)₃, Si(CH₃)₂, CH₂OCH₂, CHOH, COOCH₂,        CHCOOH, CO, CHOCH₃, O or CHOCHOCH₃,    -   R* is H, F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁,        C₆F₅, Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is H, R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br, and    -   R and R* are independent from each other.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br,    -   R′ is R,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br,    -   R′ is R,    -   R″ is R′,    -   R* is H or R′, and    -   R, R′, R″ and R* are independent from one another.

Also available are a derivative oftetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene structure of the formula(2) wherein n is 1, a derivative ofhexacyclo[6.6.1.1^(3.6).1^(10.13).0^(2.7).0^(9.14)]-4-heptadecenestructure of the formula (2) wherein n is 2, and a derivative ofoctacyclo[8.8.0.1^(2.9).1^(4.7).1^(11.18).1^(13.16).0^(3.8).0^(12.17)]-5-docosenestructure of the formula (2) wherein n is 3, each of which has the samesubstituents as those of the above-exemplified derivative ofbicyclo[2.2.1]hept-2-ene structure of the formula (2) wherein n is 0.

Examples of the cycloolefin monomers represented by the formula (3)include 5,6-bistrifluoromethylbicyclo[2.2.1]hepta-2,5-diene,perfluorobicyclo[2.2.1]hepta-2,5-diene and5,6-bistrifluoromethyl-7-oxobicyclo[2.2.1]hepta-2,5-diene.

For example, there can be mentioned the following structures.

wherein

-   -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R* is H, R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br, and    -   R and R* are independent from each other.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is CF₂, CFCF, CHCF₃, C(CF₃)₂, (CF₂)₂, (CF₂)₃, CHC₆F₅,        Si(CF₃)₂, CF₂OCF₂, CFOH, COCF₂, CFCOOCF₂, CFCOOH or CFCN,    -   R′ is R, CH₂, (CH₂)₂, (CH₂)₃, Si(CH₃)₂, CH₂OCH₂, CHOH, COOCH₂,        CHCOOH, CO, CHOCH₃, O or CHOCOCH₃,    -   R* is H, F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁,        C₆F₅, Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   Y is O, CO, NCF₃, NCH₃ or NC₆F₅,    -   R is CF₂, CFCF, CHCF₃, C(CF₃)₂, (CF₂)₂, (CF₂)₃, CHC₆F₅,        Si(CF₃)₂, CF₂OCF₂, CFOH, COCF₂, CFCOOCF₂, CFCOOH or CFCN,    -   R′ is R, CH₂, (CH₂)₂, (CH₂)₃, Si(CH₃)₂, CH₂OCH₂, CHOH, COOCH₂,        CHCOOH, CO, CHOCH₃, O or CHOCOCH₃,    -   R* is H, F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁,        C₆F₅, Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃, COOC₂F₅        (C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is CH₂, CF₂, C(CF₃)₂, O or S,

R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF (CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃, COOC₂F₅(C₅H₈),CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,

-   -   R′ is R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH or CF₂CN,    -   R′ is H, R, CH₃, C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃,        COOC(CH₃)₃, COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or        Br, and    -   R and R* are independent from each other.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br,    -   R′ is R,    -   R* is H or R′, and    -   R, R′ and R* are independent from one another.        wherein    -   X is N or P,    -   R is F, CF₃, CF₂CF₃, C₃F₇, C₄F₉, CF(CF₃)₂, C(CF₃)₃, C₆F₁₁, C₆F₅,        Si(CF₃)₃, OCF₃, COOCF₃, COOCCH₃(CF₃)₂, COOC(CF₃)₃,        COOC₂F₅(C₅H₈), CF₂OCF₃, CF₂OH, CF₂OCOCF₃, CF₂COOH, CF₂CN, CH₃,        C(CH₃)₃, Si(CH₃)₃, OCH₃, CH₂OH, COOCH₃, COOC(CH₃)₃,        COOC₂H₅(C₅H₈), CH₂OCH₃, CH₂OCOCH₃, COOH, CN, OH or Br,    -   R′ is R,    -   R″ is R′,    -   R* is H or R′, and    -   R, R′, R″ and R* are independent from one another.

Also available are a derivative oftetracyclo[4.4.0.1^(2.5).1^(7.10)]dodeca-3,8-diene structure of theformula (3) wherein n is 1, a derivative ofhexacyclo[6.6.1.1^(3.6).1^(10.13).0^(2.7).0^(9.14)]heptadeca-4,11-dienestructure of the formula (3) wherein n is 2, and a derivative ofoctacyclo[8.8.0.1^(2.9).1^(4.7).1^(11.18).1^(13.16).0^(3.8).0^(12.17)]doco-5,14-dienestructure of the formula (3) wherein n is 3, each of which has the samesubstituents as those of the above-exemplified derivative ofbicyclo[2.2.1]hepta-2,5-diene structure of the formula (3) wherein n is0.

As examples of the cycloolefin monomers represented by the formula (2)or (3), there can be further mentioned a fluorine-containingbicycloheptene derivative such as perfluorobicyclo[2.2.1]hept-2-ene, afluorine-containing bicycloheptadiene derivative such asperfluorobicyclo[2.2.1]hepta-2,5-diene, and a fluorine-containingtetracyclododecene derivative such asperfluorotetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene.

In the cycloolefin monomer, the total sum of the number of all, fluorineatoms contained in R¹ to R¹² in the formula (2) and the total sum of thenumber of all fluorine atoms contained in R¹ to R¹⁰ in the formula (3)are each preferably not less than 3.

The cycloolefin monomers represented by the formula (2) or (3) can besynthesized by subjecting fluorine-containing olefins as dienophiles toaddition reaction with cyclopentadienes, furans, thiophenes, pyrroles,etc. by the publicly known Diels-Alder reaction.

The cycloolefin monomers can also be synthesized by other processes,such as a process wherein bicycloolefins having polar group, such asalcohols, carboxylic acids, esters, ketones, aldehydes, ethers andamides, or cycloolefins, such as bicyclodienes, tetracycloolefins,tetracyclodienes, octacycloolefins and octacyclodienes, are fluorinatedusing fluorinating agents such as sulfur tetrafluoride and DAST tointroduce fluorine into cycloolefins, and a process wherein alcoholcompounds containing fluorine, carboxylic acid compounds containingfluorine, silicon compounds containing fluorine, halogenated (e.g.,brominated or iodinated) hydrocarbon compounds containing fluorine, etc.are subjected to known coupling reaction, condensation reaction oraddition reaction to introduce fluorine into cycloolefins.

Process for Preparing Fluorine-Containing Cycloolefin Polymer

The fluorine-containing cycloolefin polymer of the invention having atleast a repeated unit structure represented by the formula (1) isprepared by a process comprising subjecting at least one cycloolefinmonomer represented by the formula (2) or (3) to ring-opening metathesispolymerization and then subjecting the resulting polymer to at least oneof hydrogenation, hydrogen fluoride addition and fluorine addition.

In the present invention, two or more cylcoolefin monomers representedby the formula (2) or (3) and different in at least one of R¹ to R¹², R¹to R¹⁰, X¹ and n may be subjected to ring-opening metathesispolymerization, or at least one cycloolefin monomer wherein X¹ in theformula (2) or (3) is —CR^(a)R^(b)— and at least one cycloolefin monomerwherein X¹ in the formula (2) or (3) is —O— may be copolymerized.

In the ring-opening metathesis polymerization of at least onecycloolefin monomer represented by the formula (2) or (3) in the presentinvention, the cycloolefin monomer represented by the formula (2) or (3)may be copolymerized with:

-   -   polycyclic cycloolefins containing no fluorine, e.g.,        bicycloheptene derivatives, such as bicyclo[2.2.1]hept-2-ene,        5-methylbicyclo[2.2.1]hept-2-ene,        5-ethylbicyclo[2.2.1]hept-2-ene,        5-chlorobicyclo[2.2.1]hept-2-ene,        5-bromobicyclo[2.2.1]hept-2-ene and        5-methyl-6-methylbicyclo[2.2.1]hept-2-ene; bicycloheptadiene        derivatives, such as bicyclo[2.2.1]hepta-2,5-diene,        5-methylbicyclo[2.2.1]hepta-2,5-diene,        5-ethylbicyclo[2.2.1]hepta-2,5-diene,        5-chlorobicyclo[2.2.1]hepta-2,5-diene,        5-bromobicyclo[2.2.1]hepta-2,5-diene and        5-methyl-6-methylbicyclo[2.2.1]hepta-2,5-diene;        tetracyclododecene derivatives, such as        tetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene,        8-methyltetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene,        8-ethyltetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene,        8-chlorotetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene,        8-bromotetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene and        8-methyl-9-methyltetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene;        hexacycloheptadecene derivatives, such as        hexacyclo[6.6.1.1^(3.6).1^(10.13).0^(2.7).0^(9.14)]-4-heptadecene,        11-methylhexacyclo[6.6.1.1^(3.6).1^(10.13).0^(2.7).0^(9.14)]-4-heptadecene        and        11-ethylhexacyclo[6.6.1.1^(3.6).1^(10.13).0^(2.7).0^(9.14)]-4-heptadecene;        and octacyclodocosene derivatives, such as        octacyclo[8.8.0.1^(2.9).1^(4.7).1^(11.18).1^(13.16).0^(3.8).0^(12.17)]-5-docosene,        14-methyloctacyclo[8.8.0.1^(2.9).1^(4.7).1^(11.18).1^(13.16).0^(3.8).0^(12.17)]-5-docosene        and        14-ethyloctacyclo[8.8.0.1^(2.9).1^(4.7).1^(11.18).1^(13.16).0^(3.8).0^(12.17)]-5-docosene;        and    -   monocyclic cyloolefins containing or not containing fluorine,        e.g., cyclobutene, fluorine-containing cyclobutene such as        perfluorocyclobutene; cyclopentene, fluorine-containing        cyclopentene such as perfluorocyclopentene; cycloheptene,        fluorine-containing cycloheptene such as perfluorocycloheptene;        cyclooctene, and fluorine-containing cyclooctene such as        perfluorocyclooctene.

The polymerization catalyst used for the synthesis of thefluorine-containing cycloolefin polymer of the invention using the abovecycloolefins is not specifically restricted provided that the metathesispolymerization can be performed by the catalyst. Examples of suchcatalysts include:

-   -   tungsten type alkylidene catalysts, such as W(N-2,6-Pr^(i)        ₂C₆H₃)(CHBu^(t))(OBu^(t))₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(CHBu^(t))(OCMe₂CF₃)₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(CHBu^(t))(OCMe₂(CF₃)₂)₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OBu^(t))₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe₂CF₃)₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe₂(CF₃)2)₂,        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂Ph)(OBu^(t))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OBu^(t))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OBu^(t))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCMePh)(OCMe₂(CF₃))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OCMe₂(CF₃))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OCMe₂(CF₃))₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCMePh)(OCMe(CF₃)₂)₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OCMe₂(CF₃)₂)₂(PR₃),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OCMe(CF₃)₂)₂(PR₃), W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OCMe₂(CF₃))₂(PR₃), W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OCMe(CF₃)₂)₂(PR₃), W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OPh)₂(PR₃), or        W(N-2,6-Me₂C₆H₃)(CHCHCMePh)(OBu^(t))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OBu^(t))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OBu^(t))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCMePh)(OCMe₂(CF₃))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OCMe₂(CF₃))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OCMe₂(CF₃))₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OCMe(CF₃)₂)₂(Py),        W(N-2,6-Me₂C₆H₃)(CHCHCPh₂)(OCMe(CF₃)₂)₂(Py), W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OCMe₂(CF₃))₂(Py), W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OCMe(CF₃)₂)₂(Py) and W(N-2,6-Pr^(i)        ₂C₆H₃)(CHCHCMePh)(OPh)₂(Py) (in these formulas, Pr^(i) denotes        an isopropyl group, R denotes an alkyl group, such as methyl or        ethyl, or an alkoxy group, such as methoxy or ethoxy, Bu^(t)        denotes a tert-butyl group, Me denotes a methyl group, Ph        denotes a phenyl group, and Py denotes a pyridine group);    -   molybdenum type alkylidene catalysts, such as Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHBu^(t))(OBu^(t))₂, Mo(N-2,6-Pri^(i)        ₂C₆H₃)(CHBu^(t))(OCMe₂CF₃)₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHBu^(t))(OCMe(CF₃)₂)₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OBu^(t))₂(PR₃), Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe₂CF₃)₂(PR₃), Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe(CF₃)₂)₂(PR₃), Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OBu^(t))₂(Py), Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe₂CF₃)₂(Py) and Mo(N-2,6-Pr^(i)        ₂C₆H₃)(CHCMe₂Ph)(OCMe(CF₃)₂)₂(Py) (in these formulas, Pr^(i)        denotes an isopropyl group, R denotes an alkyl group, such as        methyl or ethyl, or an alkoxy group, such as methoxy or ethoxy,        Bu^(t) denotes a tert-butyl group, Me denotes a methyl group, Ph        denotes a phenyl group, and Py denotes a pyridine group);    -   rhenium type alkylidene catalysts, such as        Re(CBu^(t))(CHBu^(t))(O-2,6-Pr^(i) ₂C₆H₃)₂,        Re(CBu^(t))(CHBu^(t))(O-2-Bu^(t)C₆H₄)₂,        Re(CBu^(t))(CHBu^(t))(OCMe₂CF₃)₂,        Re(CBu^(t))(CHBu^(t))(OCMe(CF₃)₂)₂ and        Re(CBu^(t))(CHBu^(t))(O-2,6-Me₂C₆H₃)₂ (in these formulas, Bu^(t)        denotes a tert-butyl group);    -   tantalum type alkylidene catalysts, such as        Ta[C(Me)C(Me)CHMe₃](O-2,6-Pr^(i) ₂C₆H₃)₃Py and        Ta[C(Ph)C(Ph)CHMe₃](O-2,6-Pr^(i) ₂C₆H₃)₃Py (in these formulas,        Me denotes a methyl group, Ph denotes a phenyl group, and Py        denotes a pyridine group); and    -   ruthenium type alkylidene catalysts and titanacyclobutane        catalysts, such as Ru(CHCHCPh₂)(PPh₃)₂Cl₂ and        Ru(CHCHCPh₂)(P(C₆H₁₁)₃)₂Cl₂ (in these formulas, Ph denotes a        phenyl group).

The ring-opening metathesis catalysts mentioned above may be used singlyor as a mixture of two or more kinds.

Other than the above-mentioned ring-opening metathesis catalysts, therecan be also employed a ring-opening metathesis catalyst system that is acombination of an organic transition metal complex, a transition metalhalide or a transition metal oxide and a Lewis acid as a co-catalyst,for example, a ring-opening metathesis catalyst consisting of atransition metal halogen complex, a transition metal halide or atransition metal oxide of molybdenum, tungsten or the like, and as aco-catalyst, an organic aluminum compound, an organic tin compound or anorganometallic compound containing lithium, sodium, magnesium, zinc,cadmium, boron or the like.

For example, there can be mentioned:

-   -   catalysts of combinations of organic transition metal halogen        complexes, specifically, tungsten type halogen complexes, such        as W(N-2,6-Pr^(i) ₂C₆H₃)(thf)(OBu^(t))₂Cl₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂CF₃)₂Cl₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂(CF₃)₂)₂Cl₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OBu^(t))₂Cl₂, W(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂CF₃)₂Cl₂ and W(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂(CF₃)₂)₂Cl₂ (in these formulas, Pr^(i) denotes        an isopropyl group, Bu^(t) denotes a tert-butyl group, Me        denotes a methyl group, Ph denotes a phenyl group, and thf        denotes tetrahydrofuran), and organometallic compounds; and    -   catalysts of combinations of organic transition metal halogen        complexes, specifically, molybdenum type halogen complexes, such        as Mo(N-2,6-Pr^(i) ₂C₆H₃)(thf)(OBu^(t))₂Cl₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂CF₃)₂Cl₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe(C_(F) ₃)₂)₂Cl₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OBu^(t))₂Cl₂, Mo(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe₂CF₃)₂Cl₂ and Mo(N-2,6-Pr^(i)        ₂C₆H₃)(thf)(OCMe(CF₃)₂)₂Cl₂ (in these formulas, Pr^(i) denotes        an isopropyl group, Bu^(t) denotes a tert-butyl group, Me        denotes a methyl group, Ph denotes a phenyl group, and thf        denotes tetrahydrofuran), or WCl₆, WOCl₄, ReCl₅, MoCl₅, TiCl₄,        RuCl₃, IrCl₃ or the like, and organometallic compounds.

Examples of the organometallic compounds as co-catalysts includeorganoaluminum compounds, such as trimethylaluminum, triethylaluminum,triisobutylaluminum, trihexylaluminum, trioctylaluminum,triphenylaluminum, tribenzylaluminum, diethylaluminum monochioride,di-n-butylaluminum monochioride, diethylaluminum monobromide,diethylaluminum monoiodide, diethylaluminum monohydride, ethylaluminumsesquichloride and ethylaluminum dicholoride; organotin compounds, suchas tetramethyltin, diethyldimethyltin, tetraethyltin, dibutyldiethyltin,tetrabutyltin, tetraoctyltin, trioctyltin fluoride, trioctyltinchloride, trioctyltin bromide, trioctyltin iodide, dibutyltindifluoride, dibutyltin dichloride, dibutyltin dibromide, dibutyltindiiodide, butyltin trifluoride, butyltin trichloride, butyltintribromide and butyltin triiodide; organolithium compounds, such asn-butyllithium; organosodium compounds, such as n-pentylsodium;organomagnesium compounds, such as methylmagnesium iodide,ethylmagnesium bromide, methylmagnesium bromide, n-propylmagnesiumbromide, t-butylmagnesium chloride and allylmagnesium chloride;oranozinc compounds, such as diethylzinc; organocadminum compounds, suchas diethylcadminum; and organoboron compounds, such as trimethylboron,triethylboron and tri-n-butylboron.

In the ring-opening metathesis polymerization, the molar ratio betweenthe cycloolefin and the ring-opening metathesis catalyst is as follows:in case of the transition metal alkylidene catalyst of tungsten,molybdenum, rhenium, tantalum, ruthenium or the like or thetitanacyclobutane catalyst, the molar ratio of the cycloolefin to thetransition metal alkylidene complex is in the range of 2 to 10000,preferably 10 to 5000.

In case of the ring-opening metathesis catalyst consisting of theorganic transition metal halogen complex, the transition metal halide orthe transition metal oxide and the oranometallic compound, the molarratio of the cycloolefin to the organic transition metal halogencomplex, the transition metal halide or the transition metal oxide is inthe range of 2 to 10000, preferably 10 to 5000, and the molar ratio ofthe organometallic compound as the co-catalyst to the organic transitionmetal halogen complex, the transition metal halide or the transitionmetal oxide is in the rang of 0.1 to 10, preferably 1 to 5.

The ring-opening metathesis polymerization can be carried out in theabsence or the presence of a solvent. Examples of the solventsemployable include ethers, such as tetrahydrofuran, diethyl ether,dibutyl ether, dimethoxyethane and dioxane; aromatic hydrocarbons, suchas benzene, toluene, xylene and ethylbenzene; aliphatic hydrocarbons,such as pentane, hexane and heptane; alicyclic hydrocarbons, such ascyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane anddecalin; halogenated hydrocarbons, such as methylene dichloride,dichloroethane, dichloroethylene, tetrachloroethane, chlorobenzene andtrichlorobenzene; fluorine-containing aromatic hydrocarbons, such asfluorobenzene, difluorobenzene, hexafluorobenzene,trifluoromethylbenzene and metaxylene hexafluoride; fluorine-containingaliphatic hydrocarbons, such as perfluorohexane; fluorine-containingalicyclic hydrocarbons, such as perfluorocyclodecalin; andfluorine-containing ethers, such as perfluoro-2-butyltetrahydrofuran.These solvents may be used as a mixture of two or more kinds.

An olefin that is used as a chain transfer agent to enhance catalystefficiency may be used. Examples of such olefins include α-olefins, suchas ethylene, propylene, butene, pentene, hexene and octane, andfluorine-containing α-olefins wherein these α-olefins are substitutedwith fluorine; silicon-containing olefins, such as vinyltrimethylsilane,allyltrimethylsilane, allyltriethylsilane and allyltriisopropylsilane,and fluorine-containing silicon-containing olefins thereof; andnon-conjugated dienes, such as 1,4-pentadiene, 1,5-hexadiene and1,6-heptadiene, and fluorine-containing non-conjugated dienes whereinthese dienes are substituted with fluorine. These olefins,fluorine-containing olefins, dienes or fluorine-containing dienes may beused singly or in combination of two or more kinds.

The amount of the α-olefin, the fluorine-containing α-olefin, the dieneor the fluorine-containing diene, which is allowed to coexist, is in therange of 0.001 to 1000, preferably 0.01 to 100, based on 1 equivalent ofthe cycloolefin monomer. The amount of the α-olefin, thefluorine-containing α-olefin, the diene or the fluorine-containing dieneis in the range of 0.1 to 1000, preferably 1 to 500, based on 1equivalent of the alkylidene of the transition metal alkylidene complexor the transition metal halide.

In the ring-opening metathesis polymerization, the concentration of themonomer/the solvent for the ring-opening metathesis catalyst ispreferably in the range of 0.1 to 100 mol/liter, although it depends onthe reactivity or the solubility of the monomer used. The polymerizationreaction is carried out at a reaction temperature of usually −30 to 150°C. for a period of 1 minute to 120 hours. The reaction is terminated bythe use of deactivating agents, for example, aldehydes such asbutylaldehyde, ketones such as acetone, alcohols such as methanol, orfluorine-containing compounds thereof, whereby a ring-opening metathesispolymer solution can be obtained.

The fluorine-containing cycloolefin polymer according to the inventioncan be obtained by subjecting the ring-opening metathesis polymer to atleast one of hydrogenation, hydrogen fluoride addition and fluorineaddition.

The hydrogenation can be carried out by a process using a knownhydrogenation catalyst. The hydrogen fluoride addition and the fluorineaddition can be carried out by contacting the ring-opening metathesispolymer with hydrogen fluoride or fluorine in accordance with a knownprocess.

By subjecting the double bond of the ring-opening metathesis polymer toat least one of hydrogenation, hydrogen fluoride addition and fluorineaddition, the vacuum ultraviolet (VUV) absorption wavelength region canbe lowered. This can be readily understood from the fact that theabsorption band of the double bond is present even in the region of ArFeximer laser beam of a wavelength of 193 nm. Accordingly, in order toincrease the VUV transmittance in the region of F2 laser beam of a VUVwavelength of 157 nm as highly as possible, it becomes essential tocarry out at least one of hydrogenation, hydrogen fluoride addition andfluorine addition of the double bond of the ring-opening metathesispolymer.

The hydrogenation of the ring-opening metathesis polymer is describedbelow in detail.

Examples of the hydrogenation catalysts for the hydrogenation reactioninclude, as heterogeneous catalysts, metallic catalysts, such aspalladium, platinum, platinum oxide, rhodium and ruthenium, andsupported type metallic catalysts wherein metals such as palladium,platinum, nickel, rhodium and ruthenium are supported on carriers suchas carbon, silica, alumina, titania, magnesia, diatomaceous earth andsynthetic zeolite; and as homogeneous catalysts, nickelnaphthenate/triethyl aluminum, nickelacetylacetonato/triisobutylaluminum, cobalt octenate/n-butyllithium,titanocene dichloride/diethylaluminum chloride, rhodium acetate,dichlorobis(triphenylphosphine)palladium,chlorotris(triphenylphosphine)rhodium,dihydridotetrakis(triphenylphosphine)ruthenium,(tricyclohexylphosphine)(1,5-cyclooctadiene)(pyridine) and iridiumhaxafluorophosphate. Also available as a homogeneous catalyst is ahydrogenation catalyst comprising an organometallic complex representedby the following formula (4) and an amine compound which are held in thepresence of hydrogen.MH_(k)Q_(h)T_(p)Z_(q)  (4)

In the formula (4), M is ruthenium, rhodium, osmium, iridium, palladium,platinum or nickel.

H is hydrogen.

Q is a halogen, such as a chlorine atom, a fluorine atom, a bromine atomor an iodine atom.

T is CO, NO, toluene, acetonitrile or tetrahydrofuran.

Z is an organophosphorus compound residue represented by PR′¹R′²R′³(P isphosphorus, and R′¹, R′² and R′³ are the same or different and are eachindependently a straight-chain, branched or cyclic alkyl, alkenyl, aryl,alkoxy or aryloxy group).

Examples of the organophosphorus compounds include trimethylphosphine,triethylphosphine, triisopropylphosphine, tri-n-propylphosphine,tri-t-butylphosphine, triisobutylphosphine, tri-n-butylphosphine,tricyclohexylphosphine, triphenylphosphine, methyldiphenylphosphine,dimethylphenylphosphine, tri-o-tolylphosphine, ti-m-tolylphosphine,tri-p-tolylphosphine, diethylphenylphosphine, dichloro(ethyl)phosphine,dichloro(phenyl)phosphine, chlorodiphenylphosphine, trimethyl phosphite,triisopropyl phophite and triphenyl phosphite.

K is 0 or an integer of 1, h is an integer of 1 to 3, p is 0 or aninteger of 1, and q is an integer of 2 to 4.

Examples of the organometallic complexes represented by the formula (4)include

-   dichlorobis(triphenylphosphine)nickel,-   dichlorobis(triphenylphosphine)palladium,-   dichlorobis(triphenylphosphine)platinum,-   chlorotris(triphenyiphosphine)rhodium,-   dichlorotris(triphenylphosphine)osmium,-   dichlorohydridobis(triphenylphosphine)iridium,-   dichlorotris(triphenylphosphine)ruthenium,-   dichlorotetrakis(triphenylphosphine)ruthenium,-   trichloronitrobis(triphenylphosphine)ruthenium,-   dichlorobis(acetonitrile)bis(triphenylphosphine)ruthenium,-   dichlorobis(tetrahydrofuran)bis(triphenylphosphine)ruthenium,-   chlorohydrido(toluene)tris(triphenylphosphine)ruthenium,-   chlorohydridocarbonyltris(triphenylphosphine)ruthenium,-   chlorohydridocarbonyltris(diethylphenylphosphine)ruthenium,-   chlorohydridonitrosyltris(triphenyiphosphine)ruthenium,-   dichlorotris(trimethylphosphine)ruthenium,-   dichlorotris(triethylphosphine)ruthenium,-   dichlorotris(tricyclohexylphosphine)ruthenium,-   dichlorotris(triphenylphosphine)ruthenium,-   dichlorotris(trimethyldiphenylphosphine)ruthenium,-   dichlorotris(tridimethylphenylphosphine)ruthenium,-   dichlorotris(tri-o-tolylphosphine)ruthenium,-   dichlorotris(dichloroethylphenylphosphine)ruthenium,-   dichlorotris(dichlorophenyiphosphine)ruthenium,-   dichlorotris(trimethylphosphine)ruthenium and-   dichlorotris(triphenylphosphine)ruthenium.

Examples of the amine compounds include primary amine compounds, such asmethylamine, ethylamine, aniline, ethylenediamine and1,3-diaminocyclobutane; secondary amine compounds, such asdimethylamine, methylisopropylamine and N-methylaniline; and tertiaryamine compounds, such as trimethylamine, triethylamine, triphenylamine,N,N-dimethylaniline, pyridine and γ-picoline. Of these, tertiary aminecompounds are preferably employed. Especially when triethylamine isused, the degree of hydrogenation is remarkably enhanced.

These organometallic complexes and amine compounds can be each used incombination of two or more kinds in an arbitrary proportion.

In the hydrogenation of the ring-opening metathesis polymer, thehydrogenation catalyst is used in an amount of 5 ppm to 100% by weight,preferably 100 ppm to 20% by weight, in terms of metal, based on thering-opening metathesis polymer. When the hydrogenation catalystcomprising the organometallic complex and the amine compound is used,the amount of the organometalic complex is in the range of 5 to 50000ppm, preferably 10 to 10000 ppm, particularly preferably 50 to 1000 ppm,based on the ring-opening metathesis polymer. The amount of the aminecompound is in the range of 0.1 equivalent to 1000 equivalents,preferably 0.5 equivalent to 500 equivalents, particularly preferably 1equivalent to 100 equivalents, based on the organometallic complex.

As the hydrogenation catalyst comprising the organometallic complex andthe amine compound, a catalyst obtained by previously contacting theorganometallic complex with the amine compound can be used, but it isalso possible to add the organomtallic complex and the amine compounddirectly to the reaction system without contacting them previously.

The solvent used for the hydrogenation reaction of the ring-openingmetathesis polymer is not specifically restricted provided that thesolvent dissolves the ring-opening metathesis polymer and the solventitself is not hydrogenated. Examples of such solvents include ethers,such as tetrahydrofuran, diethyl ether, dibutyl ether anddimethoxyethane; aromatic hydrocarbons, such as benzene, toluene, xyleneand ethylbenzene; aliphatic hydrocarbons, such as pentane, hexane andheptane; alicyclic hydrocarbons, such as cyclopentane, cyclohexane,methylcyclohexane, dimethylcyclohexane and decalin; halogenatedhydrocarbons, such as methylene dichloride, dichloroethane,dichloroethylene, tetrachloroethane, chlorobenzene and trichlorobenzene;fluorine-containing aromatic hydrocarbons, such as fluorobenzene,difluorobenzene, hexafluorobenzene, trifluoromethylbenzene andmetaxylene hexafluoride; fluorine-containing aliphatic hydrocarbons,such as perfluorohexane; fluorine-containing alicyclic hydrocarbons,such as perfluorocyclodecalin; and fluorine-containing ethers, such asperfluoro-2-butyltetrahydrofuran. These solvents may be used as amixture of two or more kinds.

The hydrogenation reaction of the ring-opening metathesis polymer iscarried out at a hydrogen pressure of usually atmospheric pressure to 30MPa, preferably 0.5 to 20 MPa, particularly preferably 2 to 15 MPa, andthe reaction temperature is in the range of usually 0 to 300° C.,preferably room temperature to 250° C., particularly preferably 50 to200° C.

The fluorine addition of the ring-opening metathesis polymer isdescribed below in detail.

The hydrogen fluoride addition or the fluorine addition can be carriedout by contacting the double bond of the ring-opening metathesis polymerwith hydrogen fluoride or fluorine. Since the reaction rate of thecatalytic reaction of the ring-opening metathesis polymer with hydrogenfluoride or fluorine is high, a liquid phase/solid phase reaction or aliquid phase/liquid phase reaction is preferable to a gas phase/solidphase reaction. Further, from the viewpoint of restriction of heatremoval, a reaction in a liquid phase of a liquid medium or a reactionin a gas phase diluted with an inert gas is preferable to a reactionusing high-concentration hydrogen fluoride or fluorine.

The liquid medium of the liquid phase may be a solvent capable ofdissolving the ring-opening metathesis polymer or a solvent capable ofsuspending the polymer, and is not specifically restricted provided thatthe liquid medium is a solvent that is not reactive with hydrogenfluoride or fluorine. Examples of such liquid media include ethers, suchas tetrahydrofuran, diethyl ether, dibutyl ether and dimethoxyethane;aromatic hydrocarbons, such as benzene, toluene, xylene andethylbenzene; aliphatic hydrocarbons, such as pentane, hexane andheptane; alicyclic hydrocarbons, such as cyclopentane, cyclohexane,methylcyclohexane, dimethylcyclohexane and decalin; halogenatedhydrocarbons, such as methylene dichloride, dichloroethane,dichloroethylene, tetrachloroethane, chlorobenzene and trichlorobenzene;fluorine-containing aromatic hydrocarbons, such as fluorobenzene,difluorobenzene, hexafluorobenzene, trifluoromethylbenzene andmetaxylene hexafluoride; fluorine-containing aliphatic hydrocarbons,such as perfluorohexane; fluorine-containing alicyclic hydrocarbons,such as perfluorocyclodecalin; and fluorine-containing ethers, such asperfluoro-2-butyltetrahydrofuran. These solvents may be used as amixture of two or more kinds.

The inert gas used for diluting hydrogen fluoride or fluorine is notspecifically restricted provided that the inert gas is not reactive withhydrogen fluoride or fluorine. Examples of such inert gases includeinert gases, such as nitrogen, argon and helium, and hydrocarbon gases,such as methane, ethane and propane. These gasses may be used as amixture of two or more kinds.

The contact amount ratio between the hydrogen fluoride or fluorine andthe ring-opening metathesis polymer depends upon the amount of doublebonds, and based on at least one double bond portion, an equimolaramount of hydrogen fluoride or fluorine is used. The amount of hydrogenfluoride or fluorine used is in the range of 1 to 100 mol equivalents,preferably 1 to 20 mol equivalents, based on the number of moles of thedouble bond portion.

The temperature of the hydrogen fluoride or fluorine addition reactionto the ring-opening metathesis polymer is in the range of usually −100to 200° C., preferably room temperature to 150° C., particularlypreferably 50 to 100° C. The reaction pressure is not specificallyrestricted and is in the range of preferably atmospheric pressure to 10MPa, more preferably atmospheric pressure to 1 MPa. When thering-opening metathesis polymer is dissolved in a solvent, theconcentration of the polymer is in the range of 1 to 80% by weight,preferably 5 to 50% by weight. The reaction of a gas phase containinghydrogen fluoride or fluorine with a solid phase comprising thering-opening metathesis polymer is preferably carried out underfluidizing or stirring, but the solid may be allowed to stand still andcontacted with the gas phase to perform addition reaction.

In the present invention, after the double bonds of the ring-openingmetathesis polymer are partially hydrogenated, they may be contactedwith hydrogen fluoride or fluorine to further perform fluorine additionreaction. The amount of double bonds partially hydrogenated is not morethan 95%, preferably not more than 90%, based on the total amount of thedouble bonds. Immediately after the hydrogenation reaction, hydrogenfluoride or fluorine may be added to the hydrogenation reaction solutionto perform the addition reaction. Moreover, it is possible that thepolymer solution obtained after the hydrogenation reaction is contactedwith a poor solvent to precipitate a polymer, and then the solid polymermay be contacted with hydrogen fluoride or fluorine, or the solidpolymer is dissolved in a solvent again and may be contacted withhydrogen fluoride or fluorine.

From the fluorine-containing cycloolefin polymer obtained by the contactwith hydrogen fluoride or fluorine, excess hydrogen fluoride or fluorinecan be removed by a known alkali neutralization treatment. After theaddition reaction, the fluorine-containing cycloolefin polymer iscontacted with sodium hydroxide, sodium hydrogencarbonate, organicamines such as diethylamine, or an alkaline aqueous solution or alkalineorganic solution of pyridine, to perform neutralization and washing.Thus, the residual hydrogen fluoride or fluorine can be removed. In thistreatment, the contact is desirably carried out at a temperature of roomtemperature to 200° C., preferably room temperature to 100° C., understirring or flowing, but the conditions are not specifically limited.

When all the double bonds in the main chain olefin portion of thering-opening metathesis polymer are added with fluorine, dissociationreaction of fluorine ion takes place in the bond between fluorine atomand carbon atom by excitation energy in case of the exposure ofultraviolet rays having a wavelength of 157 nm that is vacuumultraviolet rays of high energy, and as a result, the main chain of thepolymer occasionally undergoes cleavage reaction to cause deteriorationof the polymer. Especially between carbon atoms to which thefluorine-carbon bond of the main chain is adjacent, this dissociationreaction takes place markedly. On the other hand, in the bond betweenhydrogen atom and carbon atom, the dissociation reaction hardly takesplace as compared with the above case, and it is important to allow themain chain to have a certain quantity of hydrogen-carbon bonds. In orderto prevent the polymer deterioration caused by the dissociation reactionof the fluorine ion, it is preferable to add hydrogen fluoride or topartially hydrogenate double bonds of the olefin portion in the presenceof a hydrogenation catalyst and then contact the remaining double bondswith fluorine, whereby the light resistance of the polymer in the vacuumultraviolet region is improved.

When at least one of the hydrogenation, the hydrogen fluoride additionand the fluorine addition of the ring-opening metathesis polymer iscarried out, the ring-opening metathesis polymer can be dissolved in asolvent again after isolated from the ring-opening metathesis polymersolution, but for example, hydrogenation reaction can be carried out byadding a metallic catalyst or a supported type metallic catalyst that isthe aforesaid heterogeneous catalyst or a hydrogenation catalystcomprising an organometallic complex or an organometallic complex and anamine compound that is the aforesaid homogeneous catalyst, withoutperforming isolation. In this case, after completion of the ring-openingmetathesis polymerization or the hydrogenation reaction, thering-opening metathesis catalyst or the hydrogenation catalyst remainingin the polymer can be removed by a known method. For example, availableare a filtration method, an adsorption method using an adsorbent, amethod comprising adding an organic acid such as lactic acid, a poorsolvent and water to a good solvent solution and then extracting andremoving the catalyst residue from the system at room temperature orunder heating, and a method comprising contacting a good solventsolution or a polymer slurry with a basic compound and an acid compoundand then washing the system to remove the catalyst residue.

The method to recover the fluorine-containing cycloolefin polymer fromthe fluorine-containing cycloolefin polymer solution in which at leastone of the hydrogenation, the hydrogen fluoride addition and thefluorine addition of the ring-opening metathesis polymer has beencarried out is not specifically limited, and known methods areemployable. For example, employable are a method comprising introducingthe reaction solution into a poor solvent with stirring to solidify thefluorine-containing cycloolefin polymer and recovering the polymer byfiltration, centrifugal separation, decantation or the like, a steamstripping method comprising blowing steam into the reaction solution toprecipitate the fluorine-containing cycloolefin polymer, and a methodcomprising heating the reaction solution to directly remove the solvent.

By carrying out at least one of the hydrogenation, the hydrogen fluorideaddition and the fluorine addition, a degree of hydrogenation or adegree of fluorine addition of not less than 90% can be readily reached,and it is possible to obtain a value of not less than 95%, particularlya value of not less than 99%. If the degree of hydrogenation or thedegree of fluorine addition is less than 90%, the transmission to thevacuum ultraviolet rays is lowered, and the light resistance cannot beexpected. The fluorine-containing cycloolefin polymer in which not lessthan 90% of double bonds have been subjected to hydrogenation, hydrogenfluoride addition or fluorine addition is practically excellent in thetransmission to the vacuum ultraviolet rays and the light resistance,and can be applied to thin films or coating materials employable withvacuum ultraviolet rays such as F2 laser beam. Further, thefluorine-containing cycloolefin polymer can be applied to resistpolymers employable with vacuum ultraviolet rays such as F2 laser beam.

In the present invention, the ring-opening metathesis polymer issubjected to at least one of hydrogenation, hydrogen fluoride additionand fluorine addition to obtain a hydrogenation product, a hydrogenfluoride addition product or a fluorine addition product of thering-opening metathesis polymer, and then, if necessary, the functionalgroups of the resulting product can be partially hydrolyzed to convertthe functional groups to a carboxylic acid or an alcohol. The functionalgroups to be hydrolyzed are alkoxycarbonyl, alkoxycarbonyloxy,alkoxycarbonylalkyl, alkoxycarbonyloxyalkyl, alkylcarbonyloxy,alkylsulfonyloxy, arylsulfonyloxy, alkoxy and alkoxyalkyl. Thishydrolysis may be any one of acid hydrolysis that is conducted in thepresence of an acid catalyst such as sulfuric acid, hydrochloric acid,nitric acid, toluenesulfonic acid, trifluoroacetic acid or acetic acid,alkaline hydrolysis that is conducted in the presence of an alkalinecatalyst such as sodium hydroxide, potassium hydroxide or bariumhydroxide, and neutral hydrolysis using sodium acetate, lithium iodideor the like instead of an acid or an alkali.

Owing to the hydrolysis, a thin film or a coating material comprisingthe fluorine-containing cycloolefin polymer, which is employable withvacuum ultraviolet rays such as F2 laser beam, can be improved in theadhesion properties to a frame substrate or an optical substrate such aslens. Further, a resist polymer comprising the fluorine-containingcycloolefin polymer, which is employable with vacuum ultraviolet rayssuch as F2 laser beam, can be improved in the adhesion properties to asilicon substrate or the solubility in an alkaline developing solution.

In the hydrolysis reaction, any of a water solvent and an organicsolvent can be used. Examples of the organic solvents include alcohols,such as methanol and ethanol; ketones, such as acetone; ethers, such astetrahydrofuran, diethyl ether, dibutyl ether, dimethoxyethane anddioxane; aromatic hydrocarbons, such as benzene, toluene, xylene andethylbenzene; aliphatic hydrocarbons, such as pentane, hexane, heptaneand cyclohexane; carboxylic acids, such as acetic acid; nitro compounds,such as nitromethane; pyridines, such as pyridine and lutidine;formamides, such as dimethylformamide; fluorine-containing aromatichydrocarbons, such as fluorobenzene, difluorobenzene, hexafluorobenzene,trifluoromethylbenzene and metaxylene hexafluoride; fluorine-containingaliphatic hydrocarbons, such as perfluorohexane; fluorine-containingalicyclic hydrocarbons, such as perfluorocyclodecalin; andfluorine-containing ethers, such as perfluoro-2-butyltetrahydrofuran.These solvents may be mixed with water or alcohols, or only the organicsolvent may be used. Further, these solvents may be used as a mixture oftwo or more kinds. The reaction temperature is in the range of usually 0to 300° C., preferably room temperature to 250° C.

After the acid or alkaline hydrolysis, neutralization with alkali oracid may be carried out. The method to recover the polymer from thesolution or the slurry containing the hydrogenation product, thehydrogen fluoride addition product or the fluorine addition product ofthe ring-opening metathesis polymer after the hydrolysis is notspecifically limited, and known methods are employable. In case of thesolution, employable are, for example, a method comprising introducingthe reaction solution into a poor solvent with stirring to precipitatethe hydrogenation product, the hydrogen fluoride addition product or thefluorine addition product of the ring-opening metathesis polymer andthen subjecting the resulting slurry to filtration, centrifugalseparation, decantation or the like to recover the polymer, a steamstripping method comprising blowing steam into the reaction solution toprecipitate the polymer, and a method comprising heating the reactionsolution to directly remove the solvent. In case of the slurry,employable is, for example, a method comprising subjecting the slurry tofiltration, centrifugal separation, decantation or the like to recoverthe polymer.

Uses

The fluorine-containing cycloolefin polymer of the invention hasexcellent light transmission over a wide range of visible region tovacuum ultraviolet region and has low light refractive index. Further,the polymer of the invention can be imparted with heat resistance,chemical resistance and water resistance.

Preferred examples of uses utilizing such properties of thefluorine-containing cycloolefin polymer include optical parts, thinfilms, pellicle membranes and coating materials.

Examples of the optical parts include information disc substrates, suchas photomagnetic disc, colorant type disc, music compact disc, and imagemusic simultaneous recording and reproduction disc; photographing typeor projection type lenses and mirror lenses used for camera, VTR, copymachine, OHP, projection TV and printer; lenses for picking upinformation from information discs or bar codes; automotive lamps orlenses of eye glasses and goggles; information transfer parts, such asoptical fiber and connector thereof; films and sheets used in theinformation-recording or information-display fields, such as informationrecording substrate in a shape other than disc shape (optical card),liquid crystal substrate, phase shift film, polarizing film, light guideboard and protective moisture-proof film; and reflective films such ascomposite two-layer film having high-refraction film.

The coating material is obtained by dissolving the fluorine-containingcycloolefin polymer in an appropriate solvent to give a solution, thencasting the solution on an appropriate base material or substrate anddrying the solution to form a thin film or a coating film. The thin filmand the pellicle membrane are obtained by stripping the thus formed thinfilm and the coating film.

As the solvent for the preparation of the solution, any solvent can beused without specific restriction provided that it can dissolve thefluorine-containing cycloolefin polymer. Examples of the solventsinclude fluorine-containing aromatic hydrocarbons, such as metaxylenehexafluoride, benzotrifluoride, fluorobenzene, difluorobenzene,hexafluorobenzene, trifluoromethylbenzene and metaxylene hexafluoride;fluorine-containing aliphatic hydrocarbons, such as perfluorohexane;fluorine-containing alicyclic hydrocarbons, such asperfluorocyclodecalin; fluorine-containing ethers, such asperfluoro-2-butyltetrahydrofuran; alicyclic hydrocarbons, such ascyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane anddecalin; and ketones, such as cyclohexanone.

Prior to film formation, the solution of the fluorine-containingcycloolefin polymer is desirably filtered through a filter havingappropriate pore diameters to remove solvent-insoluble impurities suchas trace level metallic component and trace level colloidal component.

The concentration of the fluorine-containing cycloolefin polymer in thesolution is in the range of usually 1 to 20% by weight, preferably 2 to10% by weight. If the olefin polymer concentration of the solution islower than the lower limit of the above range, the efficiency of filmformation or removal of impurities tends to lower. On the other hand, ifthe concentration is higher than the upper limit, the viscosity of thesolution is increased, and hence workability of film formation orremoval of impurities tends to lower.

In order to form the thin film using the fluorine-containing cycloolefinpolymer solution, a film casting method per se publicly known, such asspin coating or knife coating, is available, and it is preferable tocast the polymer solution on a smooth substrate surface such as glassplate to form a thin film. The thickness of the thin film can be readilycontrolled by changing solution viscosity, rotation speed of thesubstrate, etc. The thin film on the substrate is dried by anappropriate means such as application of hot air or irradiation withinfrared rays to remove the residual solvent.

The thickness of the thin film as a pellicle membrane is generally inthe range of 0.05 to 10 μm, and the thickness is preferably sodetermined that the transmittance to the wavelength of the shortwavelength light exposure becomes high. In case of a F2 laser beamhaving a wavelength of 157 nm, a thickness of usually 0.1 to 2 μm issuitable.

The thin film, the coating material and the pellicle membrane accordingto the invention can be used as they are, that is to say, they can beused as a single-layer thin film or coating film, or they can be used asa multi-layer film consisting of the film and a known inorganic ororganic anti-reflection film formed on one or both surfaces of the film.

The pellicle used for the process for forming a pattern by lithographyis made by spreading the thin film obtained by the above process on oneside of a pellicle frame and coating the other side with an adhesive ora double-sided tape, and the pellicle is so designed that it can befitted onto a mask.

As the pellicle frame, a frame made of a metal such as aluminum,aluminum alloy or stainless steel, a frame made of a synthetic resin ora frame made of ceramic is used, without limiting thereto.

For spreading the thin film on the pellicle frame, a known adhesive,such as a silicone resin adhesive or a fluororesin adhesive, is used.According to such a structure of the pellicle, introduction of a foreignsubstance from the outside can be prevented. Even if a foreign substanceadheres to the membrane, an image of the foreign substance is out of thefocal point in the exposure and is not transferred, so that a troublehardly occurs.

In order to prevent occurrence of dust inside the pellicle, a layer of atacky material per se publicly known can be formed on the inner side ofthe pellicle frame or the pellicle membrane. That is to say, provisionof a tacky layer on the inner side of the pellicle frame or the pelliclemembrane is advantageous in that occurrence of dust inside the pelliclecan be prevented and floating dust can be fixed and prevented fromadhesion to the mask.

In the process for forming a pattern by lithography according to theinvention, the pellicle having a pellicle membrane prepared by the aboveprocess is fitted to a photo mask or a reticle in which a circuitpattern made of a deposited film such as a chromium film is formed on aglass substrate, and the circuit pattern is transferred onto a siliconwafer coated with a resist by the exposure using an exposure lighthaving an extremely short wavelength, particularly a F2 laser beamhaving a wavelength of 157 nm.

According to the present invention, even if an exposure light having anextremely short wavelength, particularly a F2 laser beam having awavelength of 157 nm, is used, lowering of durability of the pelliclemembrane caused by photodecomposition is less brought about, and thetransmittance is good. As a result, a sharp and fine pattern can bestably formed by lithography for a relatively long period of time.

The photoresist composition of the invention uses the aforesaidfluorine-containing cycloolefin polymer as a photoresist base polymer,and for example, the composition is used as a positive photoresist usingan acid generator and a solvent together with the fluorine-containingcycloolefin polymer.

The acid generator used herein is a substance which generates Brønstedacid or Lewis acid when exposed to active radiation such as an excimerlaser beam. There is no specific limitation on the acid generator, andany acid generator selected from those heretofore known as acidgenerators for chemical amplification type photoresists can be employed.

To the photoresist composition, additives conventionally used forphotoresists, such as additional resin to improve properties of resistfilm, plasticizer, heat stabilizer, antioxidant, adhesion improver,colorant, surface active agent, anti-halation agent, organic carboxylicacid and amines, can be added within limits not detrimental to theproperties of the photoresist composition.

Using the photoresist composition of the invention, a pattern can beformed by known lithography. For example, the photoresist composition isapplied to a surface of a substrate such as a silicon wafer by aconventional means such as spin coating in such a manner that the filmthickness becomes 0.5 to 2.0 μm, and then prebaked on a hot plate at 50to 160° C. for 1 to 20 minutes, preferably at 80 to 120° C. for 1 to 10minutes, to remove the solvent, whereby a photoresist film can beformed. Subsequently, a mask for forming a desired pattern is held overthe photoresist film, then the photoresist film is irradiated withactive rays or radiation such as far ultraviolet rays, KrF excimer laserbeam, ArF excimer laser beam, F2 laser beam, X rays or electron rays,and the photoresist film is subjected to heat treatment (baking afterexposure) on a hot plate at 50 to 160° C. for 1 to 20 minutes,preferably at 80 to 120° C. for 1 to 10 minutes. Then, the exposedportion is washed with a developing solution such as an alkaline aqueoussolution of tetramethylammonium hydroxide having a concentration of 0.1to 5%, preferably 1 to 3%, in a conventional way such as immersion,paddling or spraying, whereby a relief pattern is obtained on thesubstrate.

The relief pattern formed by the use of the photoresist composition ofthe invention is extremely good in both of the resolution and thecontrast. The fluorine-containing cycloolefin polymer of the inventionis useful particularly as a photoresist base polymer for a F2 laserbeam. Moreover, by the use of the pattern formed as above as a mask, thesubstrate can be etched.

EXAMPLES

The present invention is further described with reference to thefollowing examples, but it should be construed that the invention is inno way limited to those examples.

Property values of the polymers obtained in the examples are measured bythe following methods.

Average Molecular Weight

The fluorine-containing cycloolefin polymer obtained was dissolved intetrahydrofuran, and the average molecular weight was measured with gelpermeation chromatography (GPC) using Nippon Bunko 830-R1 andUVIDEC-100-VI as detectors and columns of Shodex k-805, 804, 803 and802.5 under the conditions of room temperature and a flow rate of 1.0ml/min, followed by calibration of the molecular weight with apolystyrene standard.

Degree of Hydrogenation

A powder of the fluorine-containing cycloolefin polymer was dissolved indeutero chloroform, deutero tetrahydrofuran, hexafluorobenzene ordeutero acetone, and the integral area of an absorption spectrum ofhydrogen bonded to the main chain double bond carbon at δ of 4.5 to 7.0ppm was calculated using a 270 MHz-¹H-NMR spectrum, or the integral areaof an absorption spectrum derived from the main chain double bond carbonat δ of 90 to 160 ppm was calculated using a 67.5 MHz-¹³C-NMR spectrum.

VUV (Vacuum Ultraviolet) Absorption Spectrum

A polymer solution was applied onto a CaF₂ plate in a film thickness of0.1 to 0.8 μm by the use of a spin coater at 200 to 800 rpm and dried.Then, a VUV absorption spectrum of the resulting film was measured byActon-502 or a Bunko Keiki VU-201 type vacuum ultravioletspectrophotometer, and the film thickness was measured by a feeler typefilm thickness meter Decktack 3030, to determine an absorptioncoefficient at 157 nm.

Refractive Index

A 5 wt % polymer solution (solvent; mixed solvent of metaxylenehexafluoride/cyclohexanone (3/1)) was dropped on a 4-inch silicon waferand applied by a spin coater under the conditions of 300 rpm×60 sec,then dried in nitrogen under the conditions of 160° C.×10 min to preparea refractive index measuring sample. Then, the refractive index of thethin film sample was measured using a thin film measuring device F20-UV(manufactured by FILMETICS Co.) through refractive index spectroscopy ata measuring wavelength of 350 to 850 nm.

Visible to Ultraviolet Absorption Spectrum

A polymer solution was applied onto a CaF₂ plate in a film thickness of0.8 to 1.0 μm by the use of a spin coater at 50 to 300 rpm and dried.Then, the absorption spectrum of the resulting film was measured by aShimadzu Seisakusho UV-3100S type visible and ultravioletspectrophotometer to obtain transmittance at 400 nm and 193 nm. The filmthickness was measured by a feeler type film thickness meter Decktack3030.

Glass Transition Temperature and 5% Decomposition Temperature

The glass transition temperature and the 5% decomposition temperaturewere measured by the use of Shimadzu Seisakusho DSC-50 and TA-50.

HOMO Energy Difference

In the calculation of the HOMO energy difference, a molecular orbitalmethod calculation software MOPAC 93 was used, and keywords relating tostructure optimization, EF, LET, DDMIN=0 and GNORM=0.3, were used.

Example 1

In a nitrogen atmosphere, 5 g of5-trifluoromethylbicyclo[2.2.1]hept-2-ene synthesized in accordance withthe aforesaid process and the process of Example 7 described later wasplaced in a 100 ml flask as a cycloolefin monomer and dissolved in 50 mlof tetrahydrofuran (referred to as “THF” hereinafter), following bystirring with a magnetic stirrer bar. To the solution, 91 mg ofW(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OBU^(t))₂(PMe₃) was added as a ring-openingmetathesis polymerization catalyst, and the reaction mixture was stirredat room temperature for 16 hours. Thereafter, 69 μl of butylaldehyde wasadded, and the reaction mixture was stirred for 30 minutes to terminatethe reaction.

The obtained ring-opening metathesis polymer solution was introducedinto 500 ml of methanol to precipitate a ring-opening metathesispolymer, and the polymer was filtered, washed with methanol and dried invacuo to obtain 3.5 g of a ring-opening metathesis polymer powder.

Thereafter, in a 200 ml autoclave, 2 g of the ring-opening metathesispolymer powder was dissolved in 50 ml of decahydronaphthalene, then 4 gof 5% Pd/C was added as a hydrogenation catalyst, and hydrogenationreaction was carried out at a hydrogen pressure of 10 MPa and 140° C.for 24 hours. Then, the temperature was returned to room temperature,and the hydrogen gas was released. The hydrogenated ring-openingmetathesis polymer was filtered, and the polymer was extracted with THFby the use of a Soxhlet extractor. The extract was introduced intomethanol to precipitate the hydrogenated product of the ring-openingmetathesis polymer, followed by filtration separation and drying invacuo. Thus, 1-25 g of a white powdery hydrogenated ring-openingmetathesis polymer (fluorine-containing cycloolefin polymer) wasobtained. In the ¹H-NMR spectrum of the obtained fuorine-containingcycloolefin polymer, any peak assigned to a proton of the main chainolefin was not observed, and the degree of hydrogenation calculated fromthe ¹H-NMR spectrum was 100%. The weight-average molecular weight Mw asmeasured with GPC was 55,500, and Mw/Mn was 1.04.

A 2 wt % metaxylene hexafluoride solution of the obtainedfluorine-containing cycloolefin polymer was prepared. The solution wasdropped onto a CaF₂ substrate and applied with a spin coater at speed of800 rpm. Then, the coating substrate was dried at 160° C., and a VUVspectrum was measured. The spectrum is shown in FIG. 1. The absorptioncoefficient of the polymer at 157 nm was 1.172 μm⁻¹.

Example 2

In a nitrogen atmosphere, 5 g of5,6-bistrifluoromethylbicyclo[2.2.1]hepta-2,5-diene synthesized inaccordance with the aforesaid process and the process of Example 7described later was placed in a 100 ml flask as a cycloolefin monomerand dissolved in 50 ml of THF, following by stirring with a magneticstirrer bar. To the solution, 65 mg ofW(N-2,6-Me₂C₆H₃)(CHCHCMe₂)(OBu^(t))₂(PMe₃) was added as a ring-openingmetathesis polymerization catalyst, and the reaction mixture was stirredat room temperature for 16 hours. Thereafter, 49 μl of butylaldehyde wasadded, and the reaction mixture was stirred for 30 minutes to terminatethe reaction. The obtained ring-opening metathesis polymer solution wasintroduced into 500 ml of methanol to precipitate a ring-openingmetathesis polymer, and the polymer was filtered, washed with methanoland dried in vacuo to obtain 4.9 g of a ring-opening metathesis polymerpowder.

Thereafter, in a 200 ml autoclave, 2 g of the ring-opening metathesispolymer powder was dissolved in 50 ml of THF, then 4 g of 5% Pd/C wasadded as a hydrogenation catalyst, and hydrogenation reaction wascarried out at a hydrogen pressure of 10 MPa and 140° C. for 24 hours.Then, the temperature was returned to room temperature, and the hydrogengas was released. The hydrogenated ring-opening metathesis polymer wasfiltered and Pd/C was removed therefrom, and then the filtrate wasintroduced into methanol to precipitate the hydrogenated product of thering-opening metathesis polymer, followed by filtration separation anddrying in vacuo. Thus, 1.25 g of a white powdery hydrogenatedring-opening metathesis polymer (fluorine-containing cycloolefinpolymer) was obtained.

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain and the five-membered ring carbon was notobserved, and the degree of hydrogenation calculated from the ¹H-NMRspectrum and the ¹³C-NMR spectrum was 100%. The weight-average molecularweight Mw as measured with GPC was 57,500, and Mw/Mn was 1.04.

The obtained fluorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 1. Then, the coatingsubstrate was dried at 160° C., and a VUV spectrum was measured. Thespectrum is shown in FIG. 1. The absorption coefficient of the polymerat 157 nm was 0.190 μm⁻¹.

Example 3

In a nitrogen atmosphere, 5 g of5,6-bistrifluoromethyl-7-oxobicyclo[2.2.1]hepta-2,5-diene synthesized inaccordance with the aforesaid process and the process of Example 7described later was placed in a 100 ml flask as a cycloolefin monomerand dissolved in 50 ml of THF, following by stirring with a magneticstirrer bar. To the solution, 113 mg of Mo(N-2,6-Pr^(i)₂C₆H₃)(CHCMe₂)(OBu^(t))₂ was added as a ring-opening metathesispolymerization catalyst, and the reaction mixture was stirred at roomtemperature for 16 hours. Thereafter, 80 μl of butylaldehyde was added,and the reaction mixture was stirred for 30 minutes to terminate thereaction. The obtained ring-opening metathesis polymer solution wasintroduced into methanol and subjected to the same operations as inExample 2 to obtain 4.6 g of a ring-opening metathesis polymer powder(fluorine-containing cycloolefin polymer).

Thereafter, in a 200 ml autoclave, 2 g of the ring-opening metathesispolymer powder was subjected to hydrogenation reaction in the samemanner as in Example 2. The obtained hydrogenated ring-openingmetathesis polymer was filtered. Then, the hydrogenated ring-openingmetathesis polymer was precipitated with methanol and dried to obtain1.6 g of a white powdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain and the five-membered ring carbon was notobserved, so that the degree of hydrogenation calculated from the ¹H-NMRspectrum and the ¹³C-NMR spectrum was 100%. The weight-average molecularweight Mw as measured with GPC was 30,750, and Mw/Mn was 1.10.

A VUV spectrum of the obtained fuorine-containing cycloolefin polymerwas measured in the same manner as in Example 2. The absorptioncoefficient at 157 nm was 0.16 μm⁻¹.

Example 4

Ring-opening metathesis polymerization was carried out in the samemanner as in Example 3, except that 5 g of5-trifluoromethyl-7-oxobicyclo[2.2.1]hept-2-ene synthesized inaccordance with the aforesaid process and the process of Example 7described later was used as the cycloolefin monomer. Thus, 3.9 g of aring-opening metathesis polymer powder was obtained.

Thereafter, 2 g of the ring-opening metathesis polymer powder wassubjected to hydrogenation reaction in the same manner as in Example 3.The obtained hydrogenated ring-opening metathesis polymer was filtered.Then, the hydrogenated ring-opening metathesis polymer was precipitatedwith methanol and dried to obtain 1.36 g of a white powdery hydrogenatedring-opening metathesis polymer (fluorine-containing cycloolefinpolymer).

In the ¹H-NMR spectrum of the obtained fuorine-containing cycloolefinpolymer, any peak assigned to a proton of the main chain olefin was notobserved, so that the degree of hydrogenation calculated from the ¹H-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 27,000, and Mw/Mn was 1.05.

A VUV spectrum of the obtained fuorine-containing cycloolefin polymerwas measured in the same manner as in Example 3. The absorptioncoefficient at 157 nm was 1.082 μm⁻¹.

Example 5

The HOMO energy differences between molecular models of the hydrogenatedproducts of the ring-opening metathesis polymers synthesized in Example1 to 4, said models being shown in Table 1, were calculated by the useof a molecular orbital method calculation software MOPAC 93.

TABLE 1 HOMO HOMO HOMO Fluorine-containing energy energy energymolecular model *1 *2 (eV) *3 (eV) difference Ex. 1

−11.56 −11.09 0.47 Ex. 2

−11.97 −11.10 0.87 Ex. 3

−10.82 −10.39 0.43 Ex. 4

−11.23 −10.40 0.83 *1 Fluorine-containing molecular model correspondingto repeated unit structure of fluorine-containing polymer *2 HOMO energyof fluorine-containing molecular model *3 HOMO energy of molecular modelwherein fluorine is replaced with hydrogen

Comparative Example 1

Ring-opening metathesis polymerization was carried out in the samemanner as in Example 3, except that 5 g of5-methylbicyclo[2.2.1]hept-2-ene was used as the cycloolefin monomer.Thus, 4.9 g of a ring-opening metathesis polymer powder was obtained.

Thereafter, 2 g of the ring-opening metathesis polymer powder wassubjected to hydrogenation reaction in the same manner as in Example 3.The obtained hydrogenated ring-opening metathesis polymer was filtered.Then, the hydrogenated ring-opening metathesis polymer was precipitatedwith methanol and dried to obtain 1.89 g of a white powdery hydrogenatedring-opening metathesis polymer.

In the ¹H-NMR spectrum of the obtained hydrogenated ring-openingmetathesis polymer, any peak assigned to a proton of the main chainolefin was not observed, so that the degree of hydrogenation calculatedfrom the ¹H-NMR spectrum was 100%. The weight-average molecular weightMw as measured with GPC was 37,000, and Mw/Mn was 1.09.

A VUV spectrum was measured in the same manner as in Example 3, exceptthat a 2 wt % cyclohexane solution of the obtained hydrogenatedring-opening metathesis polymer was used instead of the 2 wt %metaxylene hexafluoride solution. The absorption coefficient at 157 nmwas 23.9 μm⁻¹.

Comparative Example 2

Ring-opening metathesis polymerization was carried out in the samemanner as in Example 3, except that 5 g of8-cyanotetracyclo[4.4.0.1^(2.5).1^(7.10)]-3-dodecene was used as thecycloolefin monomer. Thus, 4.9 g of a ring-opening metathesis polymerpowder was obtained.

Thereafter, in a 200 ml autoclave, 2 g of the ring-opening metathesispolymer powder was dissolved in 50 ml of THF, then a THF (30 ml)solution of dichlorotetrakis(triphenylphosphine)ruthenium (2.0 mg) andtriethylamine (0.8 mg) having been previously prepared was added as ahydrogenation catalyst, and hydrogenation reaction was carried out at ahydrogen pressure of 8.1 MPa and 165° C. for 5 hours. Then, thetemperature was returned to room temperature, and the hydrogen gas wasreleased. The hydrogenated ring-opening metathesis polymer solution wasintroduced into methanol to precipitate the hydrogenated ring-openingmetathesis polymer, followed by filtration and drying in vacuo. Thus,1.79 g of a white powdery hydrogenated ring-opening metathesis polymerwas obtained.

In the ¹H-NMR spectrum of the obtained hydrogenated ring-openingmetathesis polymer, any peak assigned to a proton of the main chainolefin was not observed, so that the degree of hydrogenation calculatedfrom the ¹H-NMR spectrum was 100%. The weight-average molecular weightMw as measured with GPC was 60,000, and Mw/Mn was 1.08.

A VUV spectrum was measured in the same manner as in Example 3, exceptthat a 2 wt % THF solution of the obtained hydrogenated ring-openingmetathesis polymer was used instead of the 2 wt % metaxylenehexafluoride solution. The absorption coefficient at 157 nm was 32.3μm⁻¹.

Comparative Example 3

A 2 wt % metaxylene hexafluoride solution of the ring-opening metathesispolymer powder of 5-trifluoromethylbicyclo[2.2.1]hept-2-ene obtained inExample 1 was prepared without hydrogenation of the polymer powder. Thesolution was dropped onto a CaF₂ substrate and applied with a spincoater at speed of 800 rpm. Then, the coating substrate was dried at160° C., and a VUV spectrum was measured. The absorption coefficient ofthe polymer at 157 nm was 33 μm⁻¹.

Comparative Example 4

A 2 wt % metaxylene hexafluoride solution of the ring-opening metathesispolymer powder of 5,6-bistrifluoromethylbicyclo[2.2.1]hepta-2,5-dieneobtained in Example 2 was prepared without hydrogenation of the polymerpowder. The solution was dropped onto a CaF₂ substrate and applied witha spin coater at speed of 800 rpm. Then, the coating substrate was driedat 160° C., and a VUV spectrum was measured. The absorption coefficientof the polymer at 157 nm was 43 μm⁻¹.

Example 6

The HOMO energy differences between molecular models shown in Table 2were calculated by the use of a molecular orbital method calculationsoftware MOPAC 93.

TABLE 2 HOMO HOMO HOMO Fluorine-containing energy energy energymolecular model *1 *2 (eV) *3 (eV) difference Ex. 6-1

−11.50 −11.10 0.40 Ex. 6-2

−11.17 −10.73 0.44 Ex. 6-3

−12.20 −11.10 1.10 *1 Fluorine-containing molecular model correspondingto repeated unit structure of fluorine-containing polymer *2 HOMO energyof fluorine-containing molecular model *3 HOMO energy of molecular modelwherein fluorine is replaced with hydrogen

Reference Example 1

The HOMO energy differences between molecular models shown in Table 3were calculated by the use of a molecular orbital method calculationsoftware MOPAC 93.

TABLE 3 HOMO HOMO HOMO Fluorine-containing energy energy energymolecular model *1 *2 (eV) *3 (eV) difference Ref. Ex. 1-1

−13.25 −11.10 2.15 Ref. Ex. 1-2

−13.32 −11.09 2.23 *1 Fluorine-containing molecular model correspondingto repeated unit structure of fluorine-containing polymer *2 HOMO energyof fluorine-containing molecular model *3 HOMO energy of molecular modelwherein fluorine is replaced with hydrogen

Example 7 (a) Synthesis of5,6-difluoro-5,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-ene

In a 70 ml autoclave, 6.3 g of dicyclopentadiene, 150 mg of hydroquinoneand 20 g of octafluoro-2-butene were placed, and heated at 90° C. for 1hour. Then, the resulting reaction solution was subjected to precisiondistillation to obtain 6.8 g of5,6-difluoro-5,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-ene.

¹H-NMR (δ in CDCl₃): 6.31 (2H, s), 3.30&3.23 (2H, s&s), 2.27&2.00 (2H,m&m); ¹³C-NMR (δ ppm in CDCl₃): 135.1 (dt), 134.4 (d), 133.9 (m), 122.3(ddq, J_(CF)=282.8 Hz), 122.0 (dq, J_(CF)=282.3 Hz), 103-100 (m), 100-97(m), 48.6 (d), 46.9 (d), 45.0 (bs)

(b) Synthesis of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-ene

In a 70 ml autoclave, 6.3 g of dicyclopentadiene, 150 mg of hydroquinoneand 25 g of decafluoro-2-pentene were placed, and stirred at roomtemperature for 5 days. Then, the resulting reaction solution wassubjected to precision distillation to obtain 8.7 g of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-ene.

¹H-NMR (δ in CDCl₃): 6.33&6.29 (2H, s&s), 3.48, 3.30&3.22 (2H, s, s&s),2.25&1.90 (2H, m&d); ¹³C-NMR (δ ppm in CDCl₃): 135.3 (m), 135.0 (m),134.2 (dt), 122.0 (tq, J_(CF)=281.6 Hz), 118.8 (dq, J_(CF)=287.8 Hz),112.0 (m), 104-101 (m), 101-98 (m), 49.5 (m), 49.2 (m), 48.3 (d), 47.5(quint), 47.2 (quint), 46.6 (d), 44.7 (d), 44.7 (bs)

(c) Synthesis of5-fluoro-5-pentafluoroethyl-6,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-ene

In a 70 ml autoclave, 2.6 g of cyclopentadiene and 20 g ofperfluoro-2-methyl-2-pentene were placed, and heated at 60° C. for 4hours. Then, the resulting reaction solution was subjected to precisiondistillation to obtain 7.0 g of5-fluoro-5-pentafluoroethyl-6,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-ene.

¹H-NMR (δ in CDCl₃): 6.50, 6.39&6.29 (2H, m, m&m), 3.52&3.38 (2H, d&s),2.43, 2.25&1.84 (2H, dd, d&m); ¹³C-NMR (δ ppm in CDCl₃): 138.9 (s,),138.0 (s), 135.2 (t), 134.2 (dd), 123.7 (dq, J_(CF)=285.8 Hz), 123.4(tq, J_(CF)=282.9 Hz), 123.2 (qq, J_(CF)=285.0 Hz), 121.3 (mt,J_(CF)=283.9 Hz), 114-103 (m), 68.5 (m), 51.1 (m), 50.8 (m), 50.3 (m),49.9 (m), 48.0 (s), 47.8 (d), 45.8 (bs)

(d) Synthesis of5,6-difluoro-5-trifluoromethyl-6-heptafluoroisopropyl-7-bicyclo[2.2.1]hept-2-ene

In a 70 ml autoclave, 6.0 g of dicyclopentadiene, 150 mg of hydroquinoneand 30 g of perfluoro-4-methyl-2-pentene were placed, and heated at 180°C. for 12 hours. Then, the resulting reaction solution was subjected toprecision distillation to obtain 6.5 g of5,6-difluoro-5-trifluoromethyl-6-heptafluoroisopropyl-7-bicyclo[2.2.1]hept-2-ene.

¹H-NMR (δ in CDCl₃): 6.37, 6.30&6.26 (2H, s, s&m), 3.63, 3.40, 3.29&3.23(2H, s, s, s&d), 2.23&1.94 (2H, m&m); ¹³C-NMR (δ ppm in CDCl₃): 135.8(d), 135.3 (t), 134.8 (d), 134.7 (d), 122.5 (mq, J_(CF)=281.1 Hz), 122.0(dq, J_(CF)=282.9 Hz), 120.9 (mq, J_(CF)=286.2 Hz), 120.3 (dq,J_(CF)=287.5 Hz), 120.2 (mq, J_(CF)=287.9 Hz), 105-89 (m), 51.1 (d),49.6 (d), 49.5 (d), 47.8 (d), 43.9 (s)

(e) Synthesis of5,6,6,7,7,8,8,9-octafluorotricyclo[5.2.1.0^(5.9)]deca-2-ene

In a 50 ml autoclave equipped with a magnetic stirring device, 12.27 gof cyclopentadiene, 39.38 g of perfluorocyclopropene and 0.29 g ofhydroquinone were placed, and the autoclave was pressurized withnitrogen. After stirring at 150° C. for 72 hours, the resulting reactionsolution was subjected to precision distillation to obtain 18.27 g of5,6,6,7,7,8,8,9-octafluorotricyclo[5.2.1.0^(5.9)]deca-2-ene.

¹H-NMR (δ in CDCl₃): 6.46 (2H, s), 6.11 (2H, s), 3.38 (2H, s), 3.23 (2H,s), 2.44 (1H, d), 2.19 (1H, d), 1.80 (2H, m); ¹³C-NMR (δ ppm in CDCl₃):136.6 (m), 135.1 (m), 114.1 (m, J_(CF)=279.0 Hz), 113.2 (m, J_(CF)=275.8Hz), 98.9 (m, J_(CF)=223.9 Hz), 48.9 (m), 45.1 (m), 41.4 (m)

(f) Synthesis of 5,6-bis-nonafluorobutyl-bicyclo[2.2.1]hept-2-ene

In a nitrogen atmosphere, 16.74 g oftrans-5H,6H-octadecafluoro-5-decene, 7.154 g of cyclopentadiene and0.150 g of hydroquinone were placed in a 50 ml pressure-resistantvessel, and stirred at 70° C. for 44 hours. The reaction solution wasallowed to stand still to separate the solution into two layers, and thelower layer was subjected to vacuum distillation to obtain 9.558 g of5,6-bis-nonafluorobutyl-bicyclo[2.2.1]hept-2-ene.

¹H-NMR (δ in C₆D₆): 1.30 (1H, d), 1.45 (1H, d), 2.39 (1H, d), 2.92 (1H,m), 2.96 (1H, d), 2.97 (1H, m), 5.94 (2H, m); ¹³C-NMR (δ ppm in C₆D6):43.19 (t), 43.46 (m), 43.46 (m), 43.89 (dd), 44.41 (m), 48.19 (d),109.71 (t, J_(CF)=267 Hz), 111.90 (m, J_(CF)=264 Hz), 117.9 (tt,J_(CF)=256 Hz), 118.3 (qt, J_(CF)=286 Hz), 136.1 (d), 136.4 (s)

Example 8

In a nitrogen atmosphere, 3 g of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-enesynthesized in Example 7 was placed in a 100 ml flask and dissolved in24 g of metaxylene hexafluoride, followed by stirring with a magneticstirrer bar. To the solution, 79.2 mg of Mo(N-2,6-Pr^(i)₂C₆H₃)(CHBu^(t))(OCMe(CF₃)₂)₂ was added, and the reaction was carriedout at room temperature for 3 days. Thereafter, 34 mg of butylaldehydewas added, and the reaction mixture was stirred for 30 minutes toterminate the reaction.

The obtained ring-opening metathesis polymer solution was introducedinto 500 ml of methanol to precipitate a ring-opening metathesispolymer, and the polymer was filtered, washed with methanol and dried invacuo to obtain 3.0 g of a ring-opening metathesis polymer powder.

Thereafter, in a 70 ml autoclave, 1.7 g of the ring-opening metathesispolymer powder was dissolved in THF, then 3 g of 5% Rh/C was added, andhydrogenation reaction was carried out at a hydrogen pressure of 10 MPaand 100° C. for 178 hours. Then, the temperature was returned to roomtemperature, and the hydrogen gas was released. The hydrogenatedring-opening metathesis polymer was filtered and Rh/C was removedtherefrom, and then the filtrate was introduced into methanol toprecipitate the hydrogenated product of the ring-opening metathesispolymer, followed by filtration separation and drying in vacuo. Thus,1.6 g of a white powdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer) was obtained.

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum (shown in FIG. 3) of theobtained fuorine-containing cycloolefin polymer, any peak assigned to adouble bond of the main chain carbon was not observed, so that thedegree of hydrogenation calculated from the ¹H-NMR spectrum and the¹³C-NMR spectrum was 100%. The weight-average molecular weight Mw asmeasured with GPC was 27,800, and Mw/Mn was 1.29.

A 6 wt % metaxylene hexafluoride solution of the obtainedfuorine-containing cycloolefin polymer was prepared, and the solutionwas dropped onto a CaF₂ substrate and applied with a spin coater atspeed of 500 rpm. Then, the coating substrate was dried in vacuo at 100°C., and a VUV spectrum was measured. The spectrum is shown in FIG. 2.The absorption coefficient at 157 nm was 0.086 μm⁻¹.

¹³C-NMR (δ ppm in THF-d₈): 122.9 (dq, J_(CF)=283.5), 104-102 (m), 102-99(m), 48.6 (d), 48.5 (d), 42.7 (d), 33.3 (bs), 29.6 (s), 27.8 (m), 27.4(m), 26.8 (bs), 26.3 (m)

Example 9

In a nitrogen atmosphere, 3 g of5,6-difluoro-5,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-enesynthesized in Example 7 was placed in a 100 ml flask and dissolved in24 g of metaxylene hexafluoride, followed by stirring with a magneticstirrer bar. To the solution, 103 mg of W(N-2,6-Pr^(i)₂C₆H₃)(CHCHCMe₂)(OCMe(CF₃)₂)₂(P(OMe)₃) was added, and the reaction wascarried out at room temperature for 2 days. Thereafter, 41 mg ofbutylaldehyde was added, and the reaction mixture was stirred for 30minutes to terminate the reaction. The obtained ring-opening metathesispolymer solution was introduced into methanol and subjected to the sameoperations as in Example 8 to obtain 3.0 g of a ring-opening metathesispolymer powder.

Thereafter, in a 70 ml autoclave, 0.5 g of the ring-opening metathesispolymer powder was dissolved in THF, then 2 g of 5% Rh/C was added, andhydrogenation reaction was carried out at 140° C. for 120 hours. Then,the same operations as in Example 8 were carried out to obtain 0.45 g ofa white powdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum (shown in FIG. 4) of theobtained fuorine-containing cycloolefin polymer, any peak assigned to adouble bond of the main chain carbon was not observed, so that thedegree of hydrogenation calculated from the ¹H-NMR spectrum and the¹³C-NMR spectrum was 100%. The weight-average molecular weight Mw asmeasured with GPC was 22,300, and Mw/Mn was 1.28.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 8, and a VUV spectrumwas measured. The spectrum is shown in FIG. 2. The absorptioncoefficient at 157 nm was 0.169 μm⁻¹.

¹³C-NMR (δ ppm in THF-d₈): 122.2 (dp, J_(CF)=285.7), 118.5 (tq,J_(CF)=288.2), 112.2 (mt, J_(CF)=264.2), 104-102 (m), 102-100 (m),100-99 (m), 48.8 (m), 47.3 (bd), 41.5 (m), 32.3 (m), 28.6 (s), 28-25 (m)

Example 10

In a nitrogen atmosphere, 4 g of5-fluoro-5-pentafluoroethyl-6,6-bistrifluoromethyl-7-bicyclo[2.2.1]hept-2-enesynthesized in Example 7 was placed in a 100 ml flask and dissolved in32 g of metaxylene hexafluoride, followed by stirring with a magneticstirrer bar. To the solution, 103 mg of W(N-2,6-Pr^(i)₂C₆H₃)(CHCHCMe₂)(OCMe(CF₃)₂)₂(P(OMe)₃) was added, and the reaction wascarried out at room temperature for 3 days. Thereafter, 41 mg ofbutylaldehyde was added, and the reaction mixture was stirred for 30minutes to terminate the reaction. The obtained ring-opening metathesispolymer solution was introduced into methanol and subjected to the sameoperations as in Example 8 to obtain 1.3 g of a ring-opening metathesispolymer powder.

Thereafter, in a 70 ml autoclave, 1.0 g of the ring-opening metathesispolymer powder was dissolved in THF, then 0.5 g of 5% Rh/Al₂O₃ was addedas a hydrogenation catalyst, and hydrogenation reaction was carried outat a hydrogen pressure of 12 MPa and 140° C. for 86 hours. Then, thesame operations as in Example 8 were carried out to obtain 0.9 g of awhite powdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 9,800, and Mw/Mn was 1.09.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 8, and a VUV spectrumwas measured. The absorption coefficient at 157 nm was 0.223 μm⁻¹.

Example 11

In a nitrogen atmosphere, 3 g of5,6-difluoro-5-trifluoromethyl-6-heptafluoroisopropyl-7-bicyclo[2.2.1]hept-2-enesynthesized in Example 7 was placed in a 100 ml flask and dissolved in28 g of metaxylene hexafluoride, followed by stirring with magneticstirrer bar. To the solution, 79.3 mg of Mo(N-2,6-Pr^(i)₂C₆H₃)(CHBu^(t))(OCMe(CE₃)₂)₂ was added, and the reaction was carriedout at room temperature for 3 days. Thereafter, 36 mg of butylaldehydewas added, and the reaction mixture was stirred for 30 minutes toterminate the reaction. The obtained ring-opening metathesis polymersolution was introduced into methanol and subjected to the sameoperations as in Example 10 to obtain 2.5 g of a ring-opening metathesispolymer powder.

Thereafter, in a 70 ml autoclave, 0.9 g of the ring-opening metathesispolymer powder was dissolved in THF, then 0.5 g of 5% Rh/Al₂O₃ wasadded, and hydrogenation reaction was carried out at a hydrogen pressureof 11 MPa and 140° C. for 66 hours. Then, the same operations as inExample 10 were carried out to obtain 0.8 g of a white powderyhydrogenated ring-opening metathesis polymer (fluorine-containingcycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, and the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 15,000, and Mw/Mn was 1.05.

The obtained hydrogenated ring-opening metathesis polymer was appliedonto a CaF₂ substrate in the same manner as in Example 10, and a VUVspectrum was measured. The absorption coefficient at 157 nm was 0.187μm⁻¹.

Example 12

In a nitrogen atmosphere, 7.042 g of5,6,6,7,7,8,8,9-octafluorotricyclo[5.2.1.0^(5.9)]deca-2-ene synthesizedin Example 7 was placed in a 100 ml flask and dissolved in 50 g ofmetaxylene hexafluoride, followed by stirring with a magnetic stirrerbar. To the solution, 178 mg of Mo(N-2,6-Pr^(i)₂C₆H₃)(CHBu^(t))(OCMe(CF₃)₂)₂ was added, and the reaction was carriedout at room temperature for 64 hours. Thereafter, 82 mg of butylaldehydewas added, and the reaction mixture was stirred for 30 minutes toterminate the reaction. From the obtained ring-opening metathesispolymer solution, the solvent was distilled off under reduced pressure,and the remainder was dissolved in 20 ml of acetone. The resultingsolution was introduced into methanol-water (methanol:water=1:1) andsubjected to the same operations as in Example 10 to obtain 5.64 g of aring-opening metathesis polymer powder.

Thereafter, in a 70 ml autoclave, 2 g of the ring-opening metathesispolymer powder was dissolved in THF, and hydrogenation reaction wascarried out in the same manner as in Example 10 except for replacing the5% Rh/Al₂O₃ with 0.7 g of Rh black. Then, the same operations as inExample 10 were carried out to obtain 1.6 g of a white powderyhydrogenated ring-opening metathesis polymer (fluorine-containingcycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 23,000, and Mw/Mn was 1.19.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 10, and a VUV spectrumwas measured. The absorption coefficient at 157 nm was 0.126 μm⁻¹.

Example 13

In a nitrogen atmosphere, 2.1 g of5,6-bis(nonafluorobutyl)-bicyclo[2.2.1]hept-2-ene synthesized in Example7 was placed in a 50 ml flask and dissolved in 18.2 g oftrifluoromethylbenzene, followed by stirring with a magnetic stirrerbar. To the solution, 26.2 mg of Mo(N-2,6-Pr^(i)₂C₆H₃)(CHCMe₃)(OCMe(CF₃)₂)₂ was added, and the reaction was carried outat room temperature for 6 hours. Thereafter, 14 mg of butylaldehyde wasadded, and the reaction mixture was stirred for 30 minutes to terminatethe reaction. The obtained ring-opening metathesis polymer solution wasintroduced into a methanol-1N hydrochloric acid mixed solution(methanol:1N hydrochloric acid=100:1) and subjected to the sameoperations as in Example 10 to obtain 2.0 g of a ring-opening metathesispolymer powder.

Thereafter, in a 70 ml autoclave, 2 g of the ring-opening metathesispolymer powder was dissolved in THF, and hydrogenation reaction wascarried out in the same manner as in Example 10. Then, the sameoperations as in Example 10 were carried out to obtain 1.9 g of a whitepowdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 53,000, and Mw/Mn was 1.10.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 10, and a VUV spectrumwas measured. The absorption coefficient at 157 nm was 0.091 ∥m⁻¹.

Example 14

The fluorine-containing cycloolefin polymer synthesized in Example 8 wasdissolved in metaxylene hexafluride to give a 5 wt % solution. Thesolution was filtered through a membrane filter (pore diameter: 1.0 μm)made of Teflon (registered trademark) to prepare a coating solution. Thesolution was applied to a glass substrate with a spin coater at speed of800 rpm to give a uniform thin membrane, and then heated at 80° C. for 5hours under vacuum to obtain a transparent membrane on the glasssubstrate.

An aluminum frame (inner diameter: 2 cm) of a pellicle frame coated withan adhesive layer was heated and press bonded to the above film. Aftercompletion of the bonding, the pellicle frame was separated from theglass substrate to obtain a uniform thin membrane having a thickness of0.8 μm.

A UVU spectrum of the resulting thin membrane was measured. The spectrumis shown in FIG. 5. The absorption coefficient at 157 nm was 0.050 μm⁻¹.

Example 15

In a nitrogen atmosphere, 3 g of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-eneand 1 g of decafluorocyclohexene were placed in a 100 ml flask anddissolved in 24 g of metaxylene hexafluoride, following by stirring witha magnetic stirrer bar. To the solution, 110 mg of W(N-2,6-Pr^(i)₂C₆H₃)(CHCHCMe₂)(OC(CF₃)₃)₂(P(OMe)₃) was added, and the reaction wascarried out at room temperature for 3 days. Thereafter, 34 mg ofbutylaldehyde was added, and the reaction mixture was stirred for 30minutes to terminate the reaction.

The obtained ring-opening metathesis polymer solution was introducedinto 500 ml of methanol to precipitate a ring-opening metathesispolymer, and the polymer was filtered, washed with methanol and dried invacuo to obtain 3.5 g of a ring-opening metathesis polymer powder.

Thereafter, in a 70 ml autoclave, 3.0 g of the ring-opening metathesispolymer powder was dissolved in THF, then 3 g of 5% Rh/C was added, andhydrogenation reaction was carried out at a hydrogen pressure of 10 MPaand 100° C. for 120 hours. Then, the same operations as in Example 8were carried out to obtain 3.0 g of a white powdery hydrogenatedring-opening metathesis polymer (fluorine-containing cycloolefinpolymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 35,200, and Mw/Mn was 1.30.

A 6 wt % metaxylene hexafluoride solution of the obtainedfuorine-containing cycloolefin polymer was prepared, and the solutionwas dropped onto a CaF₂ substrate and applied with a spin coater atspeed of 500 rpm. Then, the coating substrate was dried in vacuo at 100°C., and a VUV spectrum was measured. The absorption coefficient at 157nm was 0.043 μm⁻¹.

Example 16

A ring-opening metathesis polymer powder of 4.3 g was obtained in thesame manner as in Example 15, except that 1.5 g ofperfluorobicyclo[2.2.1]hept-2,5-ene was used instead of 1 g ofdecafluorocyclohexene.

Thereafter, in a 70 ml autoclave, 3.0 g of the ring-opening metathesispolymer powder was dissolved in THF, and hydrogenation reaction wascarried out in the same manner as in Example 15 to obtain 3.0 g of awhite powdery hydrogenated ring-opening metathesis polymer(fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 43,400, and Mw/Mn was 1.27.

A 6 wt % metaxylene hexafluoride solution of the obtainedfuorine-containing cycloolefin polymer was prepared, and the solutionwas dropped onto a CaF₂ substrate and applied with a spin coater atspeed of 500 rpm. Then, the coating substrate was dried in vacuo at 100°C., and a VUV spectrum was measured. The absorption coefficient at 157nm was 0.039 μm⁻¹.

Example 17

A ring-opening metathesis polymer of 4.5 g was obtained in the samemanner as in Example 15, except that 1.5 g of6-trifluoromethyl-7-oxobicyclo[2.2.1]-hept-2-ene-5-carbocylicacid-1,1-bis(trifluoromethyl)ethyl ester was used instead of 1 g ofdecafluorocyclohexene. Thereafter, in a 70 ml autoclave, 3.0 g of thering-opening metathesis polymer powder was dissolved in THF, andhydrogenation reaction was carried out in the same manner as in Example15 to obtain 3.0 g of a white powdery hydrogenated ring-openingmetathesis polymer (fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 38,900, and Mw/Mn was 1.35.

A 6 wt % metaxylene hexafluoride solution of the obtainedfuorine-containing cycloolefin polymer was prepared, and the solutionwas dropped onto a CaF₂ substrate and applied with a spin coater atspeed of 500 rpm. Then, the coating substrate was dried in vacuo at 100°C., and a VUV spectrum was measured. The absorption coefficient at 157nm was 1.23 μm⁻¹.

Example 18

In 15 g of propylene glycol monomethyl ether acetate, 2.0 g of thefluorine-containing cycloolefin polymer obtained in Example 17 and 0.04g of bis(p-tert-butylphenyl)iodonium trifluoromethanesulfonate weredissolved, and the solution was filtered through a microfilter of 0.1 μmto prepare a positive photoresist solution.

Then, the photoresist solution was applied to a silicon wafer by a spincoater and dried at 110° C. for 90 seconds on a hot plate to form apositive photoresist layer having a thickness of 0.5 μm.

The photoresist layer was selectively irradiated with an ArF excimerlaser beam (193 nm) by the use of an ArF exposure device (manufacturedby Nikon K.K., NA=0.55), then heated at 100° C. for 90 seconds,developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution for 60 seconds, washed with distilled water for 30 seconds anddried to obtain a resist pattern profile.

The exposure time in which the ratio between the line and space of 0.18μm formed by the above operations became 1:1 was measured in terms ofsensitivity (mJ/cm², energy quantity), and as a result, it was 25mJ/cm².

The sectional shape of the resist pattern of 0.18 μm formed as above wasobserved by a photomicrograph of SEM (scanning type electron microscope,manufactured by Hitachi. Ltd., S-4500). As a result, the resist patternhad a rectangular shape perpendicular to the substrate, and there was nopattern inversion.

The polymer has proved to be useful as a resist polymer for a F2 laserbeam because it has sufficient transparency at the F2 wavelength (157nm) and exhibits excellent pattern-forming agility in the ArF exposureas described above.

Example 19

The fluorine-containing cycloolefin polymer synthesized in Example 8 wasdissolved in metaxylene hexafluoride to give a 5 wt % solution, and thesolution was filtered through a membrane filter (pore diameter: 1.0 μm)made of Teflon (registered trademark) to prepare a coating solution.

The solution was uniformly applied to a glass substrate (size: 200mm×200 mm) by a spin coater at 800 rpm.

Then, the coating substrate was dried at 80° C. for 5 hours under vacuumto remove the solvent, whereby a transparent fluorine-containingcycloolefin polymer membrane was obtained on the glass plate.Thereafter, by the use of a provisional frame (external size: 220 mmsquare, internal size: 180 mm square) made of an ABS resin, theabove-obtained polymer membrane was separated from the glass substrateand a self-supporting membrane made of only the polymer was prepared.The thickness of the polymer membrane was 0.8 μm.

One side surface of an aluminum alloy pellicle frame (size: long side149 mm×short side 124 mm×height 6.3 mm, wall thickness: 2 mm) was coatedwith a fluorine type adhesive, and the fluorine-containing cycloolefinpolymer membrane was transferred to the pellicle frame from theprovisional frame to prepare a pellicle. A VUV spectrum of the thusobtained pellicle membrane was measured. The absorption coefficient at157 nm was 0.050 μm⁻¹.

Utilizing the obtained pellicle as a dust-proofing film of a mask, aresist pattern of 0.18 mm was formed by an ArF exposure device(manufactured by Nikon K.K., NA=0.55) in the same manner as in Example18. As a result, the resist pattern had a rectangular shapeperpendicular to the substrate, and there was no pattern inversion. Thefluorine-containing cycloolefin polymer of the invention has proved tobe useful as a resist polymer for a F2 laser beam because it hassufficient transparency at the F2 wavelength (157 nm) and exhibitsexcellent pattern-forming ability in the ArF exposure as describedabove.

After exposure to a laser beam of a wavelength of 157 nm at 64 mJ/cm², aVUV spectrum was measured. The absorption coefficient was 0.050 μm⁻¹,and no change was observed, so that this polymer proved to be free fromlowering of transparency caused by deterioration of the polymer andproved to have excellent light resistance.

Example 20

Ring-opening metathesis polymerization and hydrogenation reaction werecarried out in the same manner as in Example 15, except that3-trifluoromethyl-7-bicyclo[2.2.1]hept-2-ene-3-carboxylicacid-tert-butyl ester was used instead of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-ene,5,6-bistrifluoromethyl-7-oxobicyclo[2.2.1]hepta-2,5-diene was usedinstead of decafluorocyclohexene, and the amount of W(N-2,6-Pr^(i)₂C₆H₃)(CHCHCMe₂)(OC(CF₃)₃)₂(P(OMe)₃) used as the catalyst was changed to250 mg. Thus, 2.3 g of a white powdery hydrogenated ring-openingmetathesis polymer (fluorine-containing cycloolefin polymer) wasobtained.

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed, so that the degree ofhydrogenation calculated from the ¹H-NMR spectrum and the ¹³C-NMRspectrum was 100%. The weight-average molecular weight Mw as measuredwith GPC was 18,200, and Mw/Mn was 1.27.

In a 500 ml flask, 2.0 g of the fluorine-containing cycloolefin polymerwas added to a solution consisting of 200 ml of metaxylene hexafluorideand 0.4 ml of trifluoroacetic acid, and they were stirred at 70° C. for1 hour. After the solvent was distilled off, the remainder was dissolvedin metaxylene hexafluoride, and the resulting solution was added tomethanol to precipitate the polymer. The polymer was filtered and driedin vacuo to obtain 1.6 g of a white powdery hydrogenated product of thering-opening metathesis polymer having been partially hydrolyzed. In theresulting polymer, 15 mol % of ester groups were hydrolyzed. Thenumber-average molecular weight Mn of the hydrogenated product of thepartially hydrolyzed ring-opening metathesis polymer, as measured withGPC, was 16,900, and Mw/Mn was 1.29.

A 6 wt % metaxylene hexafluoride solution of the resulting partiallyhydrolyzed fluorine-containing cycloolefin polymer hydrogenated productwas prepared, and the solution was dropped onto a CaF₂ substrate andapplied with a spin coater at speed of 500 rpm. Then, the coating wasdried in vacuo at 100° C., and a VUV spectrum was measured. Theabsorption coefficient at 157 nm was 1.42 μm⁻¹.

Example 21

In 13 g of propylene glycol monomethyl ether acetate, 2.0 g of thefluorine-containing cycloolefin polymer obtained in Example 20 and 0.02g of triphenylsulfonium trifluorate were dissolved, and the solution wasfiltered through a microfilter of 0.1 μm to prepare a positivephotoresist solution.

Then, the photoresist solution was applied to a silicon wafer by a spincoater and dried at 110° C. for 90 seconds on a hot plate to form apositive photoresist layer having a thickness of 0.5 μm. The photoresistlayer was selectively irradiated with an ArF excimer laser beam (193 nm)by the use of an ArF exposure device (manufactured by Nikon K.K.,NA=0.55), then heated at 100° C. for 90 seconds, developed with a 2.38wt % tetramethylammonium hydroxide aqueous solution for 60 seconds,washed with distilled water for 30 seconds and dried to obtain a resistpattern profile.

The exposure time in which the ratio between the line and space of 0.18μm formed by the above operations became 1:1 was measured in terms ofsensitivity (mJ/cm², energy quantity), and as a result, it was 20mJ/cm².

The sectional shape of the resist pattern of 0.18 μm formed as above wasobserved by a photomicrograph of SEM (scanning type electron microscope,manufactured by Hitachi. Ltd., S-4500). As a result, the resist patternhad a rectangular shape perpendicular to the substrate, and there was nopattern inversion.

The fluorine-containing cycloolefin polymer of the invention has provedto be useful as a resist polymer for a F2 laser beam because it hassufficient transparency at the F2 wavelength (157 nm) and exhibitsexcellent pattern-forming ability in the ArF exposure as describedabove.

Example 22

In 24 g of metaxylene hexafluoride, 3 g of5,6-difluoro-5-trifluoromethyl-6-pentafluoroethyl-7-bicyclo[2.2.1]hept-2-enewas dissolved in the same manner as in Example 8. To the solution, 79.2mg of Mo(N-2,6-Pr^(i) ₂C₆H₃)(CHBu^(t))(OCMe(CF₃)₂)₂ was added, and thereaction was carried out at room temperature for 3 days. Thereafter, 34mg of butylaldehyde was added, and the reaction mixture was stirred for30 minutes to terminate the reaction. Then, the obtained ring-openingmetathesis polymer solution was subjected to the same operations as inExample 8 to precipitate a ring-opening metathesis polymer, and thepolymer was filtered, washed with methanol and dried in vacuo to obtain3.0 g of a ring-opening metathesis polymer powder.

Thereafter, in a 100 ml Teflon-lining autoclave, 2.7 g of thering-opening metathesis polymer powder was dissolved in metaxylenehexafluoride. Then, 0.35 g of a hydrogen fluoride gas was introduced,and the autoclave was pressurized with nitrogen to perform additionreaction at 30° C. for 100 hours. After the autoclave was purged withnitrogen at room temperature, the remaining hydrogen fluoride gas wasreplaced with nitrogen at 50° C. and thereby released. The reactionsolution was introduced into methanol to precipitate a hydrogen fluorideaddition product of the ring-opening metathesis polymer, and theaddition product was sufficiently washed with water and hot water,separated by filtration and dried in vacuo to obtain 2.8 g of a whitepowdery ring-opening metathesis polymer hydrogen fluoride additionproduct (fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed. The weight-averagemolecular weight Mw as measured with GPC was 32,700, and Mw/Mn was 1.39.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 8. Then, the coatingsubstrate was dried in vacuo at 100° C., and a VUV spectrum wasmeasured. The absorption coefficient at 157 nm was 0.066 μm⁻¹.

Example 23

A ring-opening metathesis polymer of 1.7 g was obtained in the samemanner as in Example 22, except that 1.7 g of the ring-openingmetathesis polymer powder obtained in Example 22 was subjected tohydrogenation reaction for 40 hours. From the ¹H-NMR spectrum, thedegree of hydrogenation of the obtained ring-opening metathesis polymerwas found to be 40%, and this ring-opening metathesis polymer was apartially hydrogenated polymer.

Thereafter, in a 100 ml Teflon-lining autoclave, the ring-openingmetathesis polymer was dissolved in metaxylene hexafluoride. Then, 0.40g of a fluorine gas was introduced, and the autoclave was pressurizedwith nitrogen to perform addition reaction at 30° C. for 100 hours.After the autoclave was purged with nitrogen at room temperature, theremaining fluorine gas was replaced with nitrogen at 50° C. and therebyreleased. The reaction solution was introduced into methanol toprecipitate a hydrogen/fluorine addition product of the ring-openingmetathesis polymer, and this addition product was washed with water andhot water, separated by filtration and dried in vacuo to obtain 1.9 g ofa white powdery ring-opening metathesis polymer hydrogen/fluorineaddition product (fluorine-containing cycloolefin polymer).

In the ¹H-NMR spectrum and the ¹³C-NMR spectrum of the obtainedfuorine-containing cycloolefin polymer, any peak assigned to a doublebond of the main chain carbon was not observed. The weight-averagemolecular weight Mw as measured with GPC was 31,500, and Mw/Mn was 1.33.

The obtained fuorine-containing cycloolefin polymer was applied onto aCaF₂ substrate in the same manner as in Example 22. Then, the coatingsubstrate was dried in vacuo at 100° C., and a VUV spectrum wasmeasured. The absorption coefficient at 157 nm was 0.073 μm⁻¹.

Example 24

The fluorine-containing cycloolefin polymers synthesized in Examples 1to 4 and Examples 8 to 13 were measured on the refractive index, lighttransmittance at wavelength of 193 nm and 400 nm, glass transitiontemperature (Tg) and 5% decomposition temperature (Td5). The results areset forth in Table 4.

TABLE 4 Polymer Polymer Polymer Polymer Polymer Polymer synthe- synthe-synthe- synthe- synthe- synthe- sized in sized in sized in sized insized in sized in Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 8 Ex. 9 Refractive 1.421.41 1.41 1.42 1.37 1.39 index Transmittance 400 nm 100 100 100 100 100100 193 nm 100 100 99 99 100 100 Tg (° C.) 47 72 44 25 105 120 Td5 (°C.) 395 399 372 374 394 389 Polymer Polymer Polymer Polymer synthesizedsynthesized synthesized synthesized in Ex. 10 in Ex. 11 in Ex. 12 in Ex.13 Refractive 1.32 1.32 1.29 1.34 index Transmittance 400 nm 100 100 100100 193 nm 100 100 100 100 Tg (° C.) 142 95 154 89 Td5 (° C.) 402 399430 328 Refractive index measuring wavelength: 633 nm Transmittancemeasuring wavelength: 400 and 193 nm

Comparative Example 5

The cycloolefin polymers synthesized in Comparative Examples 1 and 2were measured on the refractive index, light transmittance at wavelengthof 193 nm and 400 nm, glass transition temperature (Tg) and 5%decomposition temperature (Td5). The results are set forth in Table 5.

TABLKE 5 Polymer synthesized Polymer synthesized in Comp. Ex. 1 in Comp.Ex. 2 Refractive index 1.49 1.54 Transmittance 400 nm 100 99 193 nm 10090 Tg (° C.) 15 206 Td5 (° C.) 423 430 Refractive index measuringwavelength: 633 nm Transmittance measuring wavelength: 400 and 193 nm

INDUSTRIAL APPLICABILITY

The fluorine-containing cycloolefin polymer of the invention hasexcellent light transmission in the vacuum ultraviolet region. Further,the polymer of the invention is excellent in electrical properties, heatresistance and adhesion to a substrate, hardly suffers deterioration dueto photodecomposition, has excellent light resistance, and is suitablefor a pellicle, a photoresist material and an optical material which areused for semiconductor production using vacuum ultraviolet rays. Thefluorine-containing cycloolefin monomer and the process for preparing afluorine-containing cycloolefin polymer according to the invention areof industrially great value.

1. A fluorine-containing cycloolefin polymer having at least a repeatedunit structure represented by the following formula (1) and having anabsorption coefficient of not more than 3.0 μm⁻¹ at 157 nm ofultraviolet rays;

wherein at least one of R¹ to R¹² and X¹ is the following fluorine orfluorine-containing group, R¹ to R¹² are each fluorine or afluorine-containing group selected from a fluorine-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing aryl group of 1 to20 carbon atoms, a fluorine-containing and silicon-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing alkoxy group of 1to 20 carbon atoms, a fluorine-containing and ether group-containingalkyl group of 2 to 20 carbon atoms, a fluorine-containingalkoxycarbonyl group of 2 to 20 carbon atoms, a fluorine-containingalkylcarbonyl group of 2 to 20 carbon atoms, a fluorine-containing andester group-containing alkyl group of 3 to 20 carbon atoms, afluorine-containing and carboxyl group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing and cyano group-containing alkylgroup of 2 to 20 carbon atoms, a fluorine-containing andchlorine-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing and bromine-containing alkyl group of 1 to 20 carbonatoms, and a fluorine-containing and iodine-containing alkyl group of 1to 20 carbon atoms, X¹ is a fluorine-containing group selected from—CR^(a)R^(b)—, —NR^(a)— and —PR^(a)— (with the proviso that at least oneof R^(a) and R^(b) in —CR^(a)R^(b)— and R^(a) in —NR^(a)— and —PR^(a)—are each selected from fluorine, a fluorine-containing alkyl group of 1to 20 carbon atoms, a fluorine-containing and silicon-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing alkoxy group of 1to 20 carbon atoms, a fluorine-containing and ether group-containingalkyl group of 2 to 20 carbon atoms, a fluorine-containingalkoxycarbonyl group of 2 to 20 carbon atoms, a fluorine-containingalkylcarbonyl group of 2 to 20 carbon atoms, a fluorine-containing andester group-containing alkyl group of 3 to 20 carbon, afluorine-containing and carboxyl group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing and cyano group-containing alkylgroup of 2 to 20 carbon atoms, a fluorine-containing andchlorine-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing and bromine-containing alkyl group of 1 to 20 carbonatoms, and a fluorine-containing and iodine-containing alkyl group of 1to 20 carbon atoms), X¹ may be selected from —O— and —S—, at least twoof R¹, R², R¹¹ and R¹² may be bonded to each other to form a cyclicstructure, and n is 0 or an integer of 1 to
 3. 2. Thefluorine-containing cycloolefin polymer as claimed in claim 1, whereinin the formula (1), R¹ to R¹² other than R¹ to R¹² which are eachfluorine or a fluorine-containing group are each hydrogen or a groupselected from an alkyl group of 1 to 20 carbon atoms, asilicon-containing alkyl group of 1 to 20 carbon atoms, an alkoxy groupof 1 to 20 carbon atoms, an alkoxycarbonyl group of 2 to 20 carbonatoms, a carbonyl group, an alkylcarbonyl group of 2 to 20 carbon atoms,a cyano group, a cyano group-containing alkyl group of 2 to 20 carbonatoms, an ester group-containing alkyl group of 3 to 20 carbon atoms, anether group-containing alkyl group of 2 to 20 carbon atoms, ahydroxycarbonyl group, a carboxyl group-containing alkyl group of 2 to20 carbon atoms, a hydroxyl group, a hydroxyl group-containing alkylgroup of 1 to 20 carbon atoms, chlorine, bromine, iodine, achlorine-containing alkyl group of 1 to 20 carbon atoms, abromine-containing alkyl group of 1 to 20 carbon atoms and aniodine-containing alkyl group of 1 to 20 carbon atoms, when X¹ is agroup other than a fluorine-containing group, R^(a) and R^(b) are eachhydrogen or a group selected from an alkyl group of 1 to 20 carbonatoms, a silicon-containing alkyl group of 1 to 20 carbon atoms, analkoxy group of 1 to 20 carbon atoms, an alkoxycarbonyl group of 2 to 20carbon atoms, a carbonyl group, an alkylcarbonyl group of 2 to 20 carbonatoms, a cyano group, a cyano group-containing alkyl group of 2 to 20carbon atoms, an ester group-containing alkyl group of 3 to 20 carbonatoms, an ether group-containing alkyl group of 2 to 20 carbon atoms, ahydroxycarbonyl group, a carboxyl group-containing alkyl group of 2 to20 carbon atoms, a hydroxyl group, a hydroxyl group-containing alkylgroup of 1 to 20 carbon atoms, chlorine, bromine, iodine, achlorine-containing alkyl group of 1 to 20 carbon atoms, abromine-containing alkyl group of 1 to 20 carbon atoms and aniodine-containing alkyl group of 1 to 20 carbon atoms, and X¹ may beselected from —O— and —S—, and at least two of R¹, R², R¹¹ and R¹² maybe bonded to each other to form a cyclic structure.
 3. A cycloolefinmonomer of the fluorine-containing cycloolefin polymer as claimed inclaim 1, which is represented by the following formula (2) or (3):

wherein at least one of R¹ to R¹² and X¹ in the formula (2) and at leastone of R¹ to R¹⁰ and X¹ in the formula (3) are each fluorine or afluorine-containing group, R¹ to R¹² in the formula (2) and R¹ to R¹⁰ inthe formula (3) are each fluorine or a fluorine-containing groupselected from a fluorine-containing alkyl group of 1 to 20 carbon atoms,a fluorine-containing aryl group of 1 to 20 carbon atoms, afluorine-containing and silicon-containing alkyl group of 1 to 20 carbonatoms, a fluorine-containing alkoxy group of 1 to 20 carbon atoms, afluorine-containing and ether group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing alkoxycarbonyl group of 2 to 20carbon atoms, a fluorine-containing alkylcarbonyl group of 2 to 20carbon atoms, a fluorine-containing and ester group-containing alkylgroup of 3 to 20 carbon atoms, a fluorine-containing and carboxylgroup-containing alkyl group of 2 to 20 carbon atoms, afluorine-containing and cyano group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing and chlorine-containing alkyl groupof 1 to 20 carbon atoms, a fluorine-containing and bromine-containingalkyl group of 2 to 20 carbon atoms, and a fluorine-containing andiodine-containing alkyl group of 1 to 20 carbon atoms, X¹ in theformulas (2) and (3) is a fluorine-containing group selected from—CR^(a)R^(b)—, —NR^(a)— and —PR^(a)— (with the proviso that at least oneof R^(a) and R^(b) in —CR^(a)R^(b)— and R^(a) in —NR^(a)— and —PR^(a)—are each selected from fluorine, a fluorine-containing alkyl group of 1to 20 carbon atoms, a fluorine-containing and silicon-containing alkylgroup of 1 to 20 carbon atoms, a fluorine-containing and alkoxy group of1 to 20 carbon atoms, a fluorine-containing and ether group-containingalkyl group of 2 to 20 carbon atoms, a fluorine-containingalkoxycarbonyl group of 2 to 20 carbon atoms, a fluorine-containingalkylcarbonyl group of 2 to 20 carbon atoms, a fluorine-containing andester group-containing alkyl group of 3 to 20 carbon atoms, afluorine-containing and carboxyl group-containing alkyl group of 2 to 20carbon atoms, a fluorine-containing and cyano group-containing alkylgroup of 2 to 20 carbon atoms, a fluorine-containing andchlorine-containing alkyl group of 1 to 20 carbon atoms, afluorine-containing and bromine-containing alkyl group of 1 to 20 carbonatoms, and a fluorine-containing and iodine-containing alkyl group of 1to 20 carbon atoms), R¹ to R¹² other than R¹ to R¹² which are eachfluorine or a fluorine-containing group in the formula (2) and R¹ to R¹⁰other than R¹ to R¹⁰ which are each fluorine or a fluorine-containinggroup in the formula (3) are each hydrogen or a group selected from analkyl group of 1 to 20 carbon atoms, a silicon-containing alkyl group of1 to 20 carbon atoms, an alkoxy group of 1 to 20 carbon atoms, analkoxycarbonyl group of 2 to 20 carbon atoms, a carbonyl group, analkylcarbonyl group of 2 to 20 carbon atoms, a cyano group, a cyanogroup-containing alkyl group of 2 to 20 carbon atoms, an estergroup-containing alkyl group of 3 to 20 carbon atoms, an ethergroup-containing alkyl group of 2 to 20 carbon atoms, a hydroxycarbonylgroup, a carboxyl group-containing alkyl group of 2 to 20 carbon atoms,a hydroxyl group, a hydroxyl group-containing alkyl group of 1 to 20carbon atoms, chlorine, bromine, iodine, a chlorine-containing alkylgroup of 1 to 20 carbon atoms, a bromine-containing alkyl group of 1 to20 carbon atoms and an iodine-containing alkyl group of 1 to 20 carbonatoms, when X¹ is a group other than a fluorine-containing group in theformulas (2) and (3), R^(a) and R^(b) are each hydrogen or a groupselected from an alkyl group of 1 to 20 carbon atoms, asilicon-containing alkyl group of 1 to 20 carbon atoms, an alkoxy groupof 1 to 20 carbon atoms, an alkoxycarbonyl group of 2 to 20 carbonatoms, a carbonyl group, an alkylcarbonyl group of 2 to 20 carbon atoms,a cyano group, a cyano group-containing alkyl group of 2 to 20 carbonatoms, an ester group-containing alkyl group of 3 to 20 carbon atoms, anether group-containing alkyl group of 2 to 20 carbon atoms, ahydroxycarbonyl group, a carboxyl group-containing alkyl group of 2 to20 carbon atoms, a hydroxyl group, a hydroxyl group-containing alkylgroup of 1 to 20 carbon atoms, chlorine, bromine, iodine, achlorine-containing alkyl group of 1 to 20 carbon atoms, abromine-containing alkyl group of 1 to 20 carbon atoms and aniodine-containing alkyl group of 1 to 20 carbon atoms, and X¹ may beselected from —O— and —S—, R¹, R², R¹¹ and R¹² in the formula (2) may bebonded to each other to form a cyclic structure, and R¹ and R² in theformula (3) may be bonded to each other to form a cyclic structure, andn is 0 or an integer of 1 to
 3. 4. A process for preparing thefluorine-containing cycloolefin polymer as claimed in claim 1,comprising subjecting at least one cycloolefin monomer represented bythe formula (2) or (3) to ring-opening metathesis polymerization andthen subjecting the obtained ring-opening metathesis polymer to at leastone of hydrogenation, hydrogen fluoride addition and fluorine addition.5. The fluorine-containing cycloolefin polymer as claimed in claim 1,wherein the repeated unit structure of the polymer, which is representedby the formula (1), is a repeated unit structure having a feature thatthe difference in the HOMO molecular orbital energy between a molecularmodel in which methyl group is bonded to each end of the unit structureand a molecular model which has the same carbon structure as the abovemolecular model but in which fluorine is replaced with hydrogen is inthe range of 0.2 eV to 1.5 eV.
 6. The cycloolefin monomer of thefluorine-containing cycloolefin polymer as claimed in claim 3, whereinthe total sum of the number of all fluorine atoms contained in R¹ to R¹²in the formula (2) and the total sum of the number of all fluorine atomscontained in R¹ to R¹⁰ in the formula (3) are each not less than
 3. 7.The fluorine-containing cycloolefin polymer as claimed in claim 1, whichis obtained using, as starting monomers, two or more cycloolefinmonomers represented by the formula (2) or (3) and different from eachother in at least one of R¹ to R¹², R¹ to R¹⁰, X¹ and n.
 8. Thefluorine-containing cycloolefin polymer as claimed in claim 1, which isobtained using, as starting monomers, at least one cycloolefin monomerrepresented by the formula (2) or (3) wherein X¹ is —CR^(a)R^(b)— and atleast one cycloolefin monomer represented by the formula (2) or (3)wherein X¹ is —O—.
 9. The fluorine-containing cycloolefin polymer asclaimed in claim 1, which is obtained using, as starting monomers, thecycloolefin monomer represented by the formula (2) or (3) and afluorine-containing monocycloolefin.
 10. The fluorine-containingcycloolefin polymer as claimed in claim 1, which has a weight-averagemolecular weight (Mw), as measured by gel permeation chromatography(GPC), of 500 to 1,000,000 in terms of polystyrene.
 11. An optical partcomprising the fluorine-containing cycloolefin polymer of any one ofclaims 1, 2, 5, 7, 8, 9 and
 10. 12. A thin film and a coating material,each of which comprises the fluorine-containing cycloolefin polymer ofany one of claims 1, 2, 5, 7, 8, 9 and 10, and a pellicle using the thinfilm or the coating material.
 13. A photoresist composition containingthe fluorine-containing cycloolefin polymer of any one of claims 1, 2,5, 7, 8, 9 and
 10. 14. A process for forming a pattern by lithography,using at least one of the thin film, the coating material, the pellicleusing the thin film or the coating material, and the photoresistcomposition of claim
 12. 15. A process for forming a pattern bylithography, using at least one of the thin film, the coating material,the pellicle using the thin film or the coating material, and thephotoresist composition of claim 12.